Black Diamond Suspension Lift Installed-questions
#151
Guest
Posts: n/a
Re: Black Diamond Suspension Lift Installed-questions
If you look at this photo again
http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG you'll see that the
t-case yoke is forward of the frame end of the stock control arms for the
rear axle. Same is true for the front, only even more pronounced.
/Peter
"Mike Romain" <romainm@sympatico.ca> wrote in message
news:4187DE1C.7CC24B10@sympatico.ca...
> I could be mistaken, but I don't buy your explanation at all.
>
> The driveshaft pivot is up high on the t-case. The control arm front
> pivot is low below the frame. The arc the lower arm describes will make
> the driveshaft extend as it goes down.
>
> It is the lower arc's lower center that will draw the driveshaft out.
>
> I will look real close next time I see a TJ hoisted, that's for sure.
> My curiosity is up.
>
> Mike
>
> Steve wrote:
> >
> > Hi Mike,
> >
> > Peter's right on that one. The TJ lower control arms are fixed to the
> > frame between the t-case and axle. In other words, the radius of the
> > control arm arc is shorter than the radius of the drive shaft arc. When
> > the axle drops on the control arm arc, it gets closer to the t-case and
> > compresses the drive shaft.
> >
> > By the way Peter, a lowered t-case will exaggerate the drive shaft
> > compression but the shaft will compress even with the t-case cross
> > member in the stock position.
> >
> > The upper arms pull the pinion angle down as the axle drops, so distance
> > from pinion to t-case is increased a tiny bit, but this is relatively
> > insignificant compared to the amount the distance is shortened as the
> > axle drops on the lower control arm arc.
> >
> > My front shaft definitely compresses when the axle is hanging fully
down.
> >
> > Steve
> > http://xjeep.dyndns.org
> >
> > Mike Romain wrote:
> > > The TJ has an upper and lower arm so the axle does indeed drop almost
> > > straight down. The gent's photos show an upper control arm.
> > >
> > > I know the spring still sits flat at full droop because I have helped
> > > replace them.
> > >
> > > Mike
> > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > 88 Cherokee 235 BFG AT's
> > >
> > > Peter Pontbriand wrote:
> > >
> > >>But, when the axle droops it doesn't drop straight down, it moves
though an
> > >>arc. The length of the control arms is fixed, so the whole axle
assembly
> > >>essentially pivots around the frame control arm mounts. Given that, if
the
> > >>transfer case output is lower than this pivot point, the driveshaft is
going
> > >>to compress.
> > >>
> > >>/Peter
> > >>
> > >>"twaldron" <thomas@OBVIOUSrubicons.com> wrote in message
> > >>news:6pOhd.14801$bP2.8253@newssvr12.news.prodigy .com...
> > >>
> > >>>No. Your pumpkin end is lower than your xfer case end. If you droop
the
> > >>>axle, it moves further away from the xfer case output shaft and
becomes
> > >>>longer.
> > >>>
> > >>>Peter Pontbriand wrote:
> > >>>
> > >>>
> > >>>>Full droop would shorten the drive shaft on a suspension like that,
> > >>
> > >>wouldn't
> > >>
> > >>>>it? I think the t-case output is lower than the frame-end control
arm
> > >>>>mounts. I'm pretty sure my drive shafts are compressed when the TJ
is on
> > >>
> > >>a
> > >>
> > >>>>lift as compared to when it's sitting on it's wheels, even with the
> > >>
> > >>raised
> > >>
> > >>>>t-case skid.
> > >>>>
> > >>>>/Peter
> > >>>>
> > >>>>"Mike Romain" <romainm@sympatico.ca> wrote in message
> > >>>>news:4187946D.85A9BF4B@sympatico.ca...
> > >>>>
> > >>>>
> > >>>>>The oil spray is common for rust protection.
> > >>>>>
> > >>>>>Your rear pinion angle looks almost right from the angle the photo
> > >>>>>shows. It is supposed to be pointing square at the driveshaft.
> > >>>>>
> > >>>>>If you jack up the rear of the Jeep and let the axle hang in space,
it
> > >>>>>can give you an idea if the axle is long enough. There is a spline
slip
> > >>>>>joint in the axle. If it is only say 1/4 the way out at full
droop,
> > >>>>>then likely you have tons of room to raise that plate back up where
it
> > >>>>>should be.
> > >>>>>
> > >>>>>While it's drooped you could at least unbolt the t-case end and
just
> > >>>>>hand place it up higher to see if it extends enough.
> > >>>>>
> > >>>>>Mike
> > >>>>>
> > >>>>>JimG wrote:
> > >>>>>
> > >>>>>
> > >>>>>>No adjustable control arms:
> > >>>>>>
> > >>>>>>http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG
> > >>>>>>http://www.citlink.net/~gunnoes/Photos/RearAxle.JPG
> > >>>>>>
> > >>>>>>Hey Mike... notice the oil sprayed under there? This Jeep was
from
> > >>>>>>Buffalo... the guy told me that was common practice in the north
for
> > >>>>
> > >>>>rust
> > >>>>
> > >>>>
> > >>>>>>prevention. Do they do that in Canada?
> > >>>>>>
> > >>>>>>JimG
> > >>>>>>
> > >>>>>>"twaldron" wrote in message ...
> > >>>>>>
> > >>>>>>
> > >>>>>>>Here is my theory FWIW:
> > >>>>>>>
> > >>>>>>>The orig owner may have first passed on installing adj. control
arms
> > >>>>
> > >>>>and
> > >>>>
> > >>>>
> > >>>>>>>used the drop kit instead, thinking he was saving money. After
> > >>>>>>>experiencing some driveline vibes even with the drop kit, he
installed
> > >>>>>>>the CV driveshaft. JimG might have to buy some adj. control arms
to
> > >>>>>>>complete the job. Of course, I'm going on one photo that does not
show
> > >>>>>>>everything (including a drop kit) and a vivid imagination.
> > >>>>>>>
> > >>>>>>>So what of it, JimG...do you have any adj. upper control arms?
> > >>>>>>>
> > >>>>
> > >>>>
> > >>>>
> > >>>--
> > >>>_______________________________________________ ____________
> > >>>tw
> > >>>
> > >>>71 Bill Stroppe Baja Bronco
> > >>>03 TJ Rubicon - Rubicon Express 4.5"
> > >>>01 XJ Sport
> > >>>
> > >>>There is a very fine line between "hobby" and "mental illness."
> > >>>-- Dave Barry
> > >>>
> > >>>Pronunciation: 'jEp
> > >>>Function: noun
> > >>>Date: 1940
> > >>>
> > >>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> > >>>A small general-purpose motor vehicle with 80-inch wheelbase,
> > >>>1/4-ton capacity, and four-wheel drive used by the U.S. army in
> > >>>World War II.
> > >>>
> > >>>(Please remove the OBVIOUS to reply by email)
> > >>>_______________________________________________ ____________
http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG you'll see that the
t-case yoke is forward of the frame end of the stock control arms for the
rear axle. Same is true for the front, only even more pronounced.
/Peter
"Mike Romain" <romainm@sympatico.ca> wrote in message
news:4187DE1C.7CC24B10@sympatico.ca...
> I could be mistaken, but I don't buy your explanation at all.
>
> The driveshaft pivot is up high on the t-case. The control arm front
> pivot is low below the frame. The arc the lower arm describes will make
> the driveshaft extend as it goes down.
>
> It is the lower arc's lower center that will draw the driveshaft out.
>
> I will look real close next time I see a TJ hoisted, that's for sure.
> My curiosity is up.
>
> Mike
>
> Steve wrote:
> >
> > Hi Mike,
> >
> > Peter's right on that one. The TJ lower control arms are fixed to the
> > frame between the t-case and axle. In other words, the radius of the
> > control arm arc is shorter than the radius of the drive shaft arc. When
> > the axle drops on the control arm arc, it gets closer to the t-case and
> > compresses the drive shaft.
> >
> > By the way Peter, a lowered t-case will exaggerate the drive shaft
> > compression but the shaft will compress even with the t-case cross
> > member in the stock position.
> >
> > The upper arms pull the pinion angle down as the axle drops, so distance
> > from pinion to t-case is increased a tiny bit, but this is relatively
> > insignificant compared to the amount the distance is shortened as the
> > axle drops on the lower control arm arc.
> >
> > My front shaft definitely compresses when the axle is hanging fully
down.
> >
> > Steve
> > http://xjeep.dyndns.org
> >
> > Mike Romain wrote:
> > > The TJ has an upper and lower arm so the axle does indeed drop almost
> > > straight down. The gent's photos show an upper control arm.
> > >
> > > I know the spring still sits flat at full droop because I have helped
> > > replace them.
> > >
> > > Mike
> > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > 88 Cherokee 235 BFG AT's
> > >
> > > Peter Pontbriand wrote:
> > >
> > >>But, when the axle droops it doesn't drop straight down, it moves
though an
> > >>arc. The length of the control arms is fixed, so the whole axle
assembly
> > >>essentially pivots around the frame control arm mounts. Given that, if
the
> > >>transfer case output is lower than this pivot point, the driveshaft is
going
> > >>to compress.
> > >>
> > >>/Peter
> > >>
> > >>"twaldron" <thomas@OBVIOUSrubicons.com> wrote in message
> > >>news:6pOhd.14801$bP2.8253@newssvr12.news.prodigy .com...
> > >>
> > >>>No. Your pumpkin end is lower than your xfer case end. If you droop
the
> > >>>axle, it moves further away from the xfer case output shaft and
becomes
> > >>>longer.
> > >>>
> > >>>Peter Pontbriand wrote:
> > >>>
> > >>>
> > >>>>Full droop would shorten the drive shaft on a suspension like that,
> > >>
> > >>wouldn't
> > >>
> > >>>>it? I think the t-case output is lower than the frame-end control
arm
> > >>>>mounts. I'm pretty sure my drive shafts are compressed when the TJ
is on
> > >>
> > >>a
> > >>
> > >>>>lift as compared to when it's sitting on it's wheels, even with the
> > >>
> > >>raised
> > >>
> > >>>>t-case skid.
> > >>>>
> > >>>>/Peter
> > >>>>
> > >>>>"Mike Romain" <romainm@sympatico.ca> wrote in message
> > >>>>news:4187946D.85A9BF4B@sympatico.ca...
> > >>>>
> > >>>>
> > >>>>>The oil spray is common for rust protection.
> > >>>>>
> > >>>>>Your rear pinion angle looks almost right from the angle the photo
> > >>>>>shows. It is supposed to be pointing square at the driveshaft.
> > >>>>>
> > >>>>>If you jack up the rear of the Jeep and let the axle hang in space,
it
> > >>>>>can give you an idea if the axle is long enough. There is a spline
slip
> > >>>>>joint in the axle. If it is only say 1/4 the way out at full
droop,
> > >>>>>then likely you have tons of room to raise that plate back up where
it
> > >>>>>should be.
> > >>>>>
> > >>>>>While it's drooped you could at least unbolt the t-case end and
just
> > >>>>>hand place it up higher to see if it extends enough.
> > >>>>>
> > >>>>>Mike
> > >>>>>
> > >>>>>JimG wrote:
> > >>>>>
> > >>>>>
> > >>>>>>No adjustable control arms:
> > >>>>>>
> > >>>>>>http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG
> > >>>>>>http://www.citlink.net/~gunnoes/Photos/RearAxle.JPG
> > >>>>>>
> > >>>>>>Hey Mike... notice the oil sprayed under there? This Jeep was
from
> > >>>>>>Buffalo... the guy told me that was common practice in the north
for
> > >>>>
> > >>>>rust
> > >>>>
> > >>>>
> > >>>>>>prevention. Do they do that in Canada?
> > >>>>>>
> > >>>>>>JimG
> > >>>>>>
> > >>>>>>"twaldron" wrote in message ...
> > >>>>>>
> > >>>>>>
> > >>>>>>>Here is my theory FWIW:
> > >>>>>>>
> > >>>>>>>The orig owner may have first passed on installing adj. control
arms
> > >>>>
> > >>>>and
> > >>>>
> > >>>>
> > >>>>>>>used the drop kit instead, thinking he was saving money. After
> > >>>>>>>experiencing some driveline vibes even with the drop kit, he
installed
> > >>>>>>>the CV driveshaft. JimG might have to buy some adj. control arms
to
> > >>>>>>>complete the job. Of course, I'm going on one photo that does not
show
> > >>>>>>>everything (including a drop kit) and a vivid imagination.
> > >>>>>>>
> > >>>>>>>So what of it, JimG...do you have any adj. upper control arms?
> > >>>>>>>
> > >>>>
> > >>>>
> > >>>>
> > >>>--
> > >>>_______________________________________________ ____________
> > >>>tw
> > >>>
> > >>>71 Bill Stroppe Baja Bronco
> > >>>03 TJ Rubicon - Rubicon Express 4.5"
> > >>>01 XJ Sport
> > >>>
> > >>>There is a very fine line between "hobby" and "mental illness."
> > >>>-- Dave Barry
> > >>>
> > >>>Pronunciation: 'jEp
> > >>>Function: noun
> > >>>Date: 1940
> > >>>
> > >>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> > >>>A small general-purpose motor vehicle with 80-inch wheelbase,
> > >>>1/4-ton capacity, and four-wheel drive used by the U.S. army in
> > >>>World War II.
> > >>>
> > >>>(Please remove the OBVIOUS to reply by email)
> > >>>_______________________________________________ ____________
#152
Guest
Posts: n/a
Re: Black Diamond Suspension Lift Installed-questions
Exactly!
That shot shows it nice.
Here is a way you maybe able to see the physics while sitting at the
keyboard.
Take 2 pens and lay them on the table in front of you. Use your right
hand and grab the right end of the bottom pen with thumb and finger in a
pinch then put the second pen against the 1st finger's nail and hold it
there with the middle finger.
So you have thumb, pen, 1st finger, pen, middle finger which holds the
pens like the axle and control arm would fit on a rear end. Like
chopsticks but in reverse.
Then take the left hand and put your ring finger on the point of the top
pen which is where the t-case u-joint would be and grab the bottom pen
about 1/3 the way up which is where the frame mount is with the thumb
and 1st finger.
Then tilt the bottom pen down like the control arm would do.
The top pin's point will leave your left ring finger and draw away.
Mike
Peter Pontbriand wrote:
>
> If you look at this photo again
> http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG you'll see that the
> t-case yoke is forward of the frame end of the stock control arms for the
> rear axle. Same is true for the front, only even more pronounced.
>
> /Peter
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:4187DE1C.7CC24B10@sympatico.ca...
> > I could be mistaken, but I don't buy your explanation at all.
> >
> > The driveshaft pivot is up high on the t-case. The control arm front
> > pivot is low below the frame. The arc the lower arm describes will make
> > the driveshaft extend as it goes down.
> >
> > It is the lower arc's lower center that will draw the driveshaft out.
> >
> > I will look real close next time I see a TJ hoisted, that's for sure.
> > My curiosity is up.
> >
> > Mike
> >
> > Steve wrote:
> > >
> > > Hi Mike,
> > >
> > > Peter's right on that one. The TJ lower control arms are fixed to the
> > > frame between the t-case and axle. In other words, the radius of the
> > > control arm arc is shorter than the radius of the drive shaft arc. When
> > > the axle drops on the control arm arc, it gets closer to the t-case and
> > > compresses the drive shaft.
> > >
> > > By the way Peter, a lowered t-case will exaggerate the drive shaft
> > > compression but the shaft will compress even with the t-case cross
> > > member in the stock position.
> > >
> > > The upper arms pull the pinion angle down as the axle drops, so distance
> > > from pinion to t-case is increased a tiny bit, but this is relatively
> > > insignificant compared to the amount the distance is shortened as the
> > > axle drops on the lower control arm arc.
> > >
> > > My front shaft definitely compresses when the axle is hanging fully
> down.
> > >
> > > Steve
> > > http://xjeep.dyndns.org
> > >
> > > Mike Romain wrote:
> > > > The TJ has an upper and lower arm so the axle does indeed drop almost
> > > > straight down. The gent's photos show an upper control arm.
> > > >
> > > > I know the spring still sits flat at full droop because I have helped
> > > > replace them.
> > > >
> > > > Mike
> > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > 88 Cherokee 235 BFG AT's
> > > >
> > > > Peter Pontbriand wrote:
> > > >
> > > >>But, when the axle droops it doesn't drop straight down, it moves
> though an
> > > >>arc. The length of the control arms is fixed, so the whole axle
> assembly
> > > >>essentially pivots around the frame control arm mounts. Given that, if
> the
> > > >>transfer case output is lower than this pivot point, the driveshaft is
> going
> > > >>to compress.
> > > >>
> > > >>/Peter
> > > >>
> > > >>"twaldron" <thomas@OBVIOUSrubicons.com> wrote in message
> > > >>news:6pOhd.14801$bP2.8253@newssvr12.news.prodigy .com...
> > > >>
> > > >>>No. Your pumpkin end is lower than your xfer case end. If you droop
> the
> > > >>>axle, it moves further away from the xfer case output shaft and
> becomes
> > > >>>longer.
> > > >>>
> > > >>>Peter Pontbriand wrote:
> > > >>>
> > > >>>
> > > >>>>Full droop would shorten the drive shaft on a suspension like that,
> > > >>
> > > >>wouldn't
> > > >>
> > > >>>>it? I think the t-case output is lower than the frame-end control
> arm
> > > >>>>mounts. I'm pretty sure my drive shafts are compressed when the TJ
> is on
> > > >>
> > > >>a
> > > >>
> > > >>>>lift as compared to when it's sitting on it's wheels, even with the
> > > >>
> > > >>raised
> > > >>
> > > >>>>t-case skid.
> > > >>>>
> > > >>>>/Peter
> > > >>>>
> > > >>>>"Mike Romain" <romainm@sympatico.ca> wrote in message
> > > >>>>news:4187946D.85A9BF4B@sympatico.ca...
> > > >>>>
> > > >>>>
> > > >>>>>The oil spray is common for rust protection.
> > > >>>>>
> > > >>>>>Your rear pinion angle looks almost right from the angle the photo
> > > >>>>>shows. It is supposed to be pointing square at the driveshaft.
> > > >>>>>
> > > >>>>>If you jack up the rear of the Jeep and let the axle hang in space,
> it
> > > >>>>>can give you an idea if the axle is long enough. There is a spline
> slip
> > > >>>>>joint in the axle. If it is only say 1/4 the way out at full
> droop,
> > > >>>>>then likely you have tons of room to raise that plate back up where
> it
> > > >>>>>should be.
> > > >>>>>
> > > >>>>>While it's drooped you could at least unbolt the t-case end and
> just
> > > >>>>>hand place it up higher to see if it extends enough.
> > > >>>>>
> > > >>>>>Mike
> > > >>>>>
> > > >>>>>JimG wrote:
> > > >>>>>
> > > >>>>>
> > > >>>>>>No adjustable control arms:
> > > >>>>>>
> > > >>>>>>http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG
> > > >>>>>>http://www.citlink.net/~gunnoes/Photos/RearAxle.JPG
> > > >>>>>>
> > > >>>>>>Hey Mike... notice the oil sprayed under there? This Jeep was
> from
> > > >>>>>>Buffalo... the guy told me that was common practice in the north
> for
> > > >>>>
> > > >>>>rust
> > > >>>>
> > > >>>>
> > > >>>>>>prevention. Do they do that in Canada?
> > > >>>>>>
> > > >>>>>>JimG
> > > >>>>>>
> > > >>>>>>"twaldron" wrote in message ...
> > > >>>>>>
> > > >>>>>>
> > > >>>>>>>Here is my theory FWIW:
> > > >>>>>>>
> > > >>>>>>>The orig owner may have first passed on installing adj. control
> arms
> > > >>>>
> > > >>>>and
> > > >>>>
> > > >>>>
> > > >>>>>>>used the drop kit instead, thinking he was saving money. After
> > > >>>>>>>experiencing some driveline vibes even with the drop kit, he
> installed
> > > >>>>>>>the CV driveshaft. JimG might have to buy some adj. control arms
> to
> > > >>>>>>>complete the job. Of course, I'm going on one photo that does not
> show
> > > >>>>>>>everything (including a drop kit) and a vivid imagination.
> > > >>>>>>>
> > > >>>>>>>So what of it, JimG...do you have any adj. upper control arms?
> > > >>>>>>>
> > > >>>>
> > > >>>>
> > > >>>>
> > > >>>--
> > > >>>_______________________________________________ ____________
> > > >>>tw
> > > >>>
> > > >>>71 Bill Stroppe Baja Bronco
> > > >>>03 TJ Rubicon - Rubicon Express 4.5"
> > > >>>01 XJ Sport
> > > >>>
> > > >>>There is a very fine line between "hobby" and "mental illness."
> > > >>>-- Dave Barry
> > > >>>
> > > >>>Pronunciation: 'jEp
> > > >>>Function: noun
> > > >>>Date: 1940
> > > >>>
> > > >>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> > > >>>A small general-purpose motor vehicle with 80-inch wheelbase,
> > > >>>1/4-ton capacity, and four-wheel drive used by the U.S. army in
> > > >>>World War II.
> > > >>>
> > > >>>(Please remove the OBVIOUS to reply by email)
> > > >>>_______________________________________________ ____________
That shot shows it nice.
Here is a way you maybe able to see the physics while sitting at the
keyboard.
Take 2 pens and lay them on the table in front of you. Use your right
hand and grab the right end of the bottom pen with thumb and finger in a
pinch then put the second pen against the 1st finger's nail and hold it
there with the middle finger.
So you have thumb, pen, 1st finger, pen, middle finger which holds the
pens like the axle and control arm would fit on a rear end. Like
chopsticks but in reverse.
Then take the left hand and put your ring finger on the point of the top
pen which is where the t-case u-joint would be and grab the bottom pen
about 1/3 the way up which is where the frame mount is with the thumb
and 1st finger.
Then tilt the bottom pen down like the control arm would do.
The top pin's point will leave your left ring finger and draw away.
Mike
Peter Pontbriand wrote:
>
> If you look at this photo again
> http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG you'll see that the
> t-case yoke is forward of the frame end of the stock control arms for the
> rear axle. Same is true for the front, only even more pronounced.
>
> /Peter
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:4187DE1C.7CC24B10@sympatico.ca...
> > I could be mistaken, but I don't buy your explanation at all.
> >
> > The driveshaft pivot is up high on the t-case. The control arm front
> > pivot is low below the frame. The arc the lower arm describes will make
> > the driveshaft extend as it goes down.
> >
> > It is the lower arc's lower center that will draw the driveshaft out.
> >
> > I will look real close next time I see a TJ hoisted, that's for sure.
> > My curiosity is up.
> >
> > Mike
> >
> > Steve wrote:
> > >
> > > Hi Mike,
> > >
> > > Peter's right on that one. The TJ lower control arms are fixed to the
> > > frame between the t-case and axle. In other words, the radius of the
> > > control arm arc is shorter than the radius of the drive shaft arc. When
> > > the axle drops on the control arm arc, it gets closer to the t-case and
> > > compresses the drive shaft.
> > >
> > > By the way Peter, a lowered t-case will exaggerate the drive shaft
> > > compression but the shaft will compress even with the t-case cross
> > > member in the stock position.
> > >
> > > The upper arms pull the pinion angle down as the axle drops, so distance
> > > from pinion to t-case is increased a tiny bit, but this is relatively
> > > insignificant compared to the amount the distance is shortened as the
> > > axle drops on the lower control arm arc.
> > >
> > > My front shaft definitely compresses when the axle is hanging fully
> down.
> > >
> > > Steve
> > > http://xjeep.dyndns.org
> > >
> > > Mike Romain wrote:
> > > > The TJ has an upper and lower arm so the axle does indeed drop almost
> > > > straight down. The gent's photos show an upper control arm.
> > > >
> > > > I know the spring still sits flat at full droop because I have helped
> > > > replace them.
> > > >
> > > > Mike
> > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > 88 Cherokee 235 BFG AT's
> > > >
> > > > Peter Pontbriand wrote:
> > > >
> > > >>But, when the axle droops it doesn't drop straight down, it moves
> though an
> > > >>arc. The length of the control arms is fixed, so the whole axle
> assembly
> > > >>essentially pivots around the frame control arm mounts. Given that, if
> the
> > > >>transfer case output is lower than this pivot point, the driveshaft is
> going
> > > >>to compress.
> > > >>
> > > >>/Peter
> > > >>
> > > >>"twaldron" <thomas@OBVIOUSrubicons.com> wrote in message
> > > >>news:6pOhd.14801$bP2.8253@newssvr12.news.prodigy .com...
> > > >>
> > > >>>No. Your pumpkin end is lower than your xfer case end. If you droop
> the
> > > >>>axle, it moves further away from the xfer case output shaft and
> becomes
> > > >>>longer.
> > > >>>
> > > >>>Peter Pontbriand wrote:
> > > >>>
> > > >>>
> > > >>>>Full droop would shorten the drive shaft on a suspension like that,
> > > >>
> > > >>wouldn't
> > > >>
> > > >>>>it? I think the t-case output is lower than the frame-end control
> arm
> > > >>>>mounts. I'm pretty sure my drive shafts are compressed when the TJ
> is on
> > > >>
> > > >>a
> > > >>
> > > >>>>lift as compared to when it's sitting on it's wheels, even with the
> > > >>
> > > >>raised
> > > >>
> > > >>>>t-case skid.
> > > >>>>
> > > >>>>/Peter
> > > >>>>
> > > >>>>"Mike Romain" <romainm@sympatico.ca> wrote in message
> > > >>>>news:4187946D.85A9BF4B@sympatico.ca...
> > > >>>>
> > > >>>>
> > > >>>>>The oil spray is common for rust protection.
> > > >>>>>
> > > >>>>>Your rear pinion angle looks almost right from the angle the photo
> > > >>>>>shows. It is supposed to be pointing square at the driveshaft.
> > > >>>>>
> > > >>>>>If you jack up the rear of the Jeep and let the axle hang in space,
> it
> > > >>>>>can give you an idea if the axle is long enough. There is a spline
> slip
> > > >>>>>joint in the axle. If it is only say 1/4 the way out at full
> droop,
> > > >>>>>then likely you have tons of room to raise that plate back up where
> it
> > > >>>>>should be.
> > > >>>>>
> > > >>>>>While it's drooped you could at least unbolt the t-case end and
> just
> > > >>>>>hand place it up higher to see if it extends enough.
> > > >>>>>
> > > >>>>>Mike
> > > >>>>>
> > > >>>>>JimG wrote:
> > > >>>>>
> > > >>>>>
> > > >>>>>>No adjustable control arms:
> > > >>>>>>
> > > >>>>>>http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG
> > > >>>>>>http://www.citlink.net/~gunnoes/Photos/RearAxle.JPG
> > > >>>>>>
> > > >>>>>>Hey Mike... notice the oil sprayed under there? This Jeep was
> from
> > > >>>>>>Buffalo... the guy told me that was common practice in the north
> for
> > > >>>>
> > > >>>>rust
> > > >>>>
> > > >>>>
> > > >>>>>>prevention. Do they do that in Canada?
> > > >>>>>>
> > > >>>>>>JimG
> > > >>>>>>
> > > >>>>>>"twaldron" wrote in message ...
> > > >>>>>>
> > > >>>>>>
> > > >>>>>>>Here is my theory FWIW:
> > > >>>>>>>
> > > >>>>>>>The orig owner may have first passed on installing adj. control
> arms
> > > >>>>
> > > >>>>and
> > > >>>>
> > > >>>>
> > > >>>>>>>used the drop kit instead, thinking he was saving money. After
> > > >>>>>>>experiencing some driveline vibes even with the drop kit, he
> installed
> > > >>>>>>>the CV driveshaft. JimG might have to buy some adj. control arms
> to
> > > >>>>>>>complete the job. Of course, I'm going on one photo that does not
> show
> > > >>>>>>>everything (including a drop kit) and a vivid imagination.
> > > >>>>>>>
> > > >>>>>>>So what of it, JimG...do you have any adj. upper control arms?
> > > >>>>>>>
> > > >>>>
> > > >>>>
> > > >>>>
> > > >>>--
> > > >>>_______________________________________________ ____________
> > > >>>tw
> > > >>>
> > > >>>71 Bill Stroppe Baja Bronco
> > > >>>03 TJ Rubicon - Rubicon Express 4.5"
> > > >>>01 XJ Sport
> > > >>>
> > > >>>There is a very fine line between "hobby" and "mental illness."
> > > >>>-- Dave Barry
> > > >>>
> > > >>>Pronunciation: 'jEp
> > > >>>Function: noun
> > > >>>Date: 1940
> > > >>>
> > > >>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> > > >>>A small general-purpose motor vehicle with 80-inch wheelbase,
> > > >>>1/4-ton capacity, and four-wheel drive used by the U.S. army in
> > > >>>World War II.
> > > >>>
> > > >>>(Please remove the OBVIOUS to reply by email)
> > > >>>_______________________________________________ ____________
#153
Guest
Posts: n/a
Re: Black Diamond Suspension Lift Installed-questions
Exactly!
That shot shows it nice.
Here is a way you maybe able to see the physics while sitting at the
keyboard.
Take 2 pens and lay them on the table in front of you. Use your right
hand and grab the right end of the bottom pen with thumb and finger in a
pinch then put the second pen against the 1st finger's nail and hold it
there with the middle finger.
So you have thumb, pen, 1st finger, pen, middle finger which holds the
pens like the axle and control arm would fit on a rear end. Like
chopsticks but in reverse.
Then take the left hand and put your ring finger on the point of the top
pen which is where the t-case u-joint would be and grab the bottom pen
about 1/3 the way up which is where the frame mount is with the thumb
and 1st finger.
Then tilt the bottom pen down like the control arm would do.
The top pin's point will leave your left ring finger and draw away.
Mike
Peter Pontbriand wrote:
>
> If you look at this photo again
> http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG you'll see that the
> t-case yoke is forward of the frame end of the stock control arms for the
> rear axle. Same is true for the front, only even more pronounced.
>
> /Peter
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:4187DE1C.7CC24B10@sympatico.ca...
> > I could be mistaken, but I don't buy your explanation at all.
> >
> > The driveshaft pivot is up high on the t-case. The control arm front
> > pivot is low below the frame. The arc the lower arm describes will make
> > the driveshaft extend as it goes down.
> >
> > It is the lower arc's lower center that will draw the driveshaft out.
> >
> > I will look real close next time I see a TJ hoisted, that's for sure.
> > My curiosity is up.
> >
> > Mike
> >
> > Steve wrote:
> > >
> > > Hi Mike,
> > >
> > > Peter's right on that one. The TJ lower control arms are fixed to the
> > > frame between the t-case and axle. In other words, the radius of the
> > > control arm arc is shorter than the radius of the drive shaft arc. When
> > > the axle drops on the control arm arc, it gets closer to the t-case and
> > > compresses the drive shaft.
> > >
> > > By the way Peter, a lowered t-case will exaggerate the drive shaft
> > > compression but the shaft will compress even with the t-case cross
> > > member in the stock position.
> > >
> > > The upper arms pull the pinion angle down as the axle drops, so distance
> > > from pinion to t-case is increased a tiny bit, but this is relatively
> > > insignificant compared to the amount the distance is shortened as the
> > > axle drops on the lower control arm arc.
> > >
> > > My front shaft definitely compresses when the axle is hanging fully
> down.
> > >
> > > Steve
> > > http://xjeep.dyndns.org
> > >
> > > Mike Romain wrote:
> > > > The TJ has an upper and lower arm so the axle does indeed drop almost
> > > > straight down. The gent's photos show an upper control arm.
> > > >
> > > > I know the spring still sits flat at full droop because I have helped
> > > > replace them.
> > > >
> > > > Mike
> > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > 88 Cherokee 235 BFG AT's
> > > >
> > > > Peter Pontbriand wrote:
> > > >
> > > >>But, when the axle droops it doesn't drop straight down, it moves
> though an
> > > >>arc. The length of the control arms is fixed, so the whole axle
> assembly
> > > >>essentially pivots around the frame control arm mounts. Given that, if
> the
> > > >>transfer case output is lower than this pivot point, the driveshaft is
> going
> > > >>to compress.
> > > >>
> > > >>/Peter
> > > >>
> > > >>"twaldron" <thomas@OBVIOUSrubicons.com> wrote in message
> > > >>news:6pOhd.14801$bP2.8253@newssvr12.news.prodigy .com...
> > > >>
> > > >>>No. Your pumpkin end is lower than your xfer case end. If you droop
> the
> > > >>>axle, it moves further away from the xfer case output shaft and
> becomes
> > > >>>longer.
> > > >>>
> > > >>>Peter Pontbriand wrote:
> > > >>>
> > > >>>
> > > >>>>Full droop would shorten the drive shaft on a suspension like that,
> > > >>
> > > >>wouldn't
> > > >>
> > > >>>>it? I think the t-case output is lower than the frame-end control
> arm
> > > >>>>mounts. I'm pretty sure my drive shafts are compressed when the TJ
> is on
> > > >>
> > > >>a
> > > >>
> > > >>>>lift as compared to when it's sitting on it's wheels, even with the
> > > >>
> > > >>raised
> > > >>
> > > >>>>t-case skid.
> > > >>>>
> > > >>>>/Peter
> > > >>>>
> > > >>>>"Mike Romain" <romainm@sympatico.ca> wrote in message
> > > >>>>news:4187946D.85A9BF4B@sympatico.ca...
> > > >>>>
> > > >>>>
> > > >>>>>The oil spray is common for rust protection.
> > > >>>>>
> > > >>>>>Your rear pinion angle looks almost right from the angle the photo
> > > >>>>>shows. It is supposed to be pointing square at the driveshaft.
> > > >>>>>
> > > >>>>>If you jack up the rear of the Jeep and let the axle hang in space,
> it
> > > >>>>>can give you an idea if the axle is long enough. There is a spline
> slip
> > > >>>>>joint in the axle. If it is only say 1/4 the way out at full
> droop,
> > > >>>>>then likely you have tons of room to raise that plate back up where
> it
> > > >>>>>should be.
> > > >>>>>
> > > >>>>>While it's drooped you could at least unbolt the t-case end and
> just
> > > >>>>>hand place it up higher to see if it extends enough.
> > > >>>>>
> > > >>>>>Mike
> > > >>>>>
> > > >>>>>JimG wrote:
> > > >>>>>
> > > >>>>>
> > > >>>>>>No adjustable control arms:
> > > >>>>>>
> > > >>>>>>http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG
> > > >>>>>>http://www.citlink.net/~gunnoes/Photos/RearAxle.JPG
> > > >>>>>>
> > > >>>>>>Hey Mike... notice the oil sprayed under there? This Jeep was
> from
> > > >>>>>>Buffalo... the guy told me that was common practice in the north
> for
> > > >>>>
> > > >>>>rust
> > > >>>>
> > > >>>>
> > > >>>>>>prevention. Do they do that in Canada?
> > > >>>>>>
> > > >>>>>>JimG
> > > >>>>>>
> > > >>>>>>"twaldron" wrote in message ...
> > > >>>>>>
> > > >>>>>>
> > > >>>>>>>Here is my theory FWIW:
> > > >>>>>>>
> > > >>>>>>>The orig owner may have first passed on installing adj. control
> arms
> > > >>>>
> > > >>>>and
> > > >>>>
> > > >>>>
> > > >>>>>>>used the drop kit instead, thinking he was saving money. After
> > > >>>>>>>experiencing some driveline vibes even with the drop kit, he
> installed
> > > >>>>>>>the CV driveshaft. JimG might have to buy some adj. control arms
> to
> > > >>>>>>>complete the job. Of course, I'm going on one photo that does not
> show
> > > >>>>>>>everything (including a drop kit) and a vivid imagination.
> > > >>>>>>>
> > > >>>>>>>So what of it, JimG...do you have any adj. upper control arms?
> > > >>>>>>>
> > > >>>>
> > > >>>>
> > > >>>>
> > > >>>--
> > > >>>_______________________________________________ ____________
> > > >>>tw
> > > >>>
> > > >>>71 Bill Stroppe Baja Bronco
> > > >>>03 TJ Rubicon - Rubicon Express 4.5"
> > > >>>01 XJ Sport
> > > >>>
> > > >>>There is a very fine line between "hobby" and "mental illness."
> > > >>>-- Dave Barry
> > > >>>
> > > >>>Pronunciation: 'jEp
> > > >>>Function: noun
> > > >>>Date: 1940
> > > >>>
> > > >>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> > > >>>A small general-purpose motor vehicle with 80-inch wheelbase,
> > > >>>1/4-ton capacity, and four-wheel drive used by the U.S. army in
> > > >>>World War II.
> > > >>>
> > > >>>(Please remove the OBVIOUS to reply by email)
> > > >>>_______________________________________________ ____________
That shot shows it nice.
Here is a way you maybe able to see the physics while sitting at the
keyboard.
Take 2 pens and lay them on the table in front of you. Use your right
hand and grab the right end of the bottom pen with thumb and finger in a
pinch then put the second pen against the 1st finger's nail and hold it
there with the middle finger.
So you have thumb, pen, 1st finger, pen, middle finger which holds the
pens like the axle and control arm would fit on a rear end. Like
chopsticks but in reverse.
Then take the left hand and put your ring finger on the point of the top
pen which is where the t-case u-joint would be and grab the bottom pen
about 1/3 the way up which is where the frame mount is with the thumb
and 1st finger.
Then tilt the bottom pen down like the control arm would do.
The top pin's point will leave your left ring finger and draw away.
Mike
Peter Pontbriand wrote:
>
> If you look at this photo again
> http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG you'll see that the
> t-case yoke is forward of the frame end of the stock control arms for the
> rear axle. Same is true for the front, only even more pronounced.
>
> /Peter
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:4187DE1C.7CC24B10@sympatico.ca...
> > I could be mistaken, but I don't buy your explanation at all.
> >
> > The driveshaft pivot is up high on the t-case. The control arm front
> > pivot is low below the frame. The arc the lower arm describes will make
> > the driveshaft extend as it goes down.
> >
> > It is the lower arc's lower center that will draw the driveshaft out.
> >
> > I will look real close next time I see a TJ hoisted, that's for sure.
> > My curiosity is up.
> >
> > Mike
> >
> > Steve wrote:
> > >
> > > Hi Mike,
> > >
> > > Peter's right on that one. The TJ lower control arms are fixed to the
> > > frame between the t-case and axle. In other words, the radius of the
> > > control arm arc is shorter than the radius of the drive shaft arc. When
> > > the axle drops on the control arm arc, it gets closer to the t-case and
> > > compresses the drive shaft.
> > >
> > > By the way Peter, a lowered t-case will exaggerate the drive shaft
> > > compression but the shaft will compress even with the t-case cross
> > > member in the stock position.
> > >
> > > The upper arms pull the pinion angle down as the axle drops, so distance
> > > from pinion to t-case is increased a tiny bit, but this is relatively
> > > insignificant compared to the amount the distance is shortened as the
> > > axle drops on the lower control arm arc.
> > >
> > > My front shaft definitely compresses when the axle is hanging fully
> down.
> > >
> > > Steve
> > > http://xjeep.dyndns.org
> > >
> > > Mike Romain wrote:
> > > > The TJ has an upper and lower arm so the axle does indeed drop almost
> > > > straight down. The gent's photos show an upper control arm.
> > > >
> > > > I know the spring still sits flat at full droop because I have helped
> > > > replace them.
> > > >
> > > > Mike
> > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > 88 Cherokee 235 BFG AT's
> > > >
> > > > Peter Pontbriand wrote:
> > > >
> > > >>But, when the axle droops it doesn't drop straight down, it moves
> though an
> > > >>arc. The length of the control arms is fixed, so the whole axle
> assembly
> > > >>essentially pivots around the frame control arm mounts. Given that, if
> the
> > > >>transfer case output is lower than this pivot point, the driveshaft is
> going
> > > >>to compress.
> > > >>
> > > >>/Peter
> > > >>
> > > >>"twaldron" <thomas@OBVIOUSrubicons.com> wrote in message
> > > >>news:6pOhd.14801$bP2.8253@newssvr12.news.prodigy .com...
> > > >>
> > > >>>No. Your pumpkin end is lower than your xfer case end. If you droop
> the
> > > >>>axle, it moves further away from the xfer case output shaft and
> becomes
> > > >>>longer.
> > > >>>
> > > >>>Peter Pontbriand wrote:
> > > >>>
> > > >>>
> > > >>>>Full droop would shorten the drive shaft on a suspension like that,
> > > >>
> > > >>wouldn't
> > > >>
> > > >>>>it? I think the t-case output is lower than the frame-end control
> arm
> > > >>>>mounts. I'm pretty sure my drive shafts are compressed when the TJ
> is on
> > > >>
> > > >>a
> > > >>
> > > >>>>lift as compared to when it's sitting on it's wheels, even with the
> > > >>
> > > >>raised
> > > >>
> > > >>>>t-case skid.
> > > >>>>
> > > >>>>/Peter
> > > >>>>
> > > >>>>"Mike Romain" <romainm@sympatico.ca> wrote in message
> > > >>>>news:4187946D.85A9BF4B@sympatico.ca...
> > > >>>>
> > > >>>>
> > > >>>>>The oil spray is common for rust protection.
> > > >>>>>
> > > >>>>>Your rear pinion angle looks almost right from the angle the photo
> > > >>>>>shows. It is supposed to be pointing square at the driveshaft.
> > > >>>>>
> > > >>>>>If you jack up the rear of the Jeep and let the axle hang in space,
> it
> > > >>>>>can give you an idea if the axle is long enough. There is a spline
> slip
> > > >>>>>joint in the axle. If it is only say 1/4 the way out at full
> droop,
> > > >>>>>then likely you have tons of room to raise that plate back up where
> it
> > > >>>>>should be.
> > > >>>>>
> > > >>>>>While it's drooped you could at least unbolt the t-case end and
> just
> > > >>>>>hand place it up higher to see if it extends enough.
> > > >>>>>
> > > >>>>>Mike
> > > >>>>>
> > > >>>>>JimG wrote:
> > > >>>>>
> > > >>>>>
> > > >>>>>>No adjustable control arms:
> > > >>>>>>
> > > >>>>>>http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG
> > > >>>>>>http://www.citlink.net/~gunnoes/Photos/RearAxle.JPG
> > > >>>>>>
> > > >>>>>>Hey Mike... notice the oil sprayed under there? This Jeep was
> from
> > > >>>>>>Buffalo... the guy told me that was common practice in the north
> for
> > > >>>>
> > > >>>>rust
> > > >>>>
> > > >>>>
> > > >>>>>>prevention. Do they do that in Canada?
> > > >>>>>>
> > > >>>>>>JimG
> > > >>>>>>
> > > >>>>>>"twaldron" wrote in message ...
> > > >>>>>>
> > > >>>>>>
> > > >>>>>>>Here is my theory FWIW:
> > > >>>>>>>
> > > >>>>>>>The orig owner may have first passed on installing adj. control
> arms
> > > >>>>
> > > >>>>and
> > > >>>>
> > > >>>>
> > > >>>>>>>used the drop kit instead, thinking he was saving money. After
> > > >>>>>>>experiencing some driveline vibes even with the drop kit, he
> installed
> > > >>>>>>>the CV driveshaft. JimG might have to buy some adj. control arms
> to
> > > >>>>>>>complete the job. Of course, I'm going on one photo that does not
> show
> > > >>>>>>>everything (including a drop kit) and a vivid imagination.
> > > >>>>>>>
> > > >>>>>>>So what of it, JimG...do you have any adj. upper control arms?
> > > >>>>>>>
> > > >>>>
> > > >>>>
> > > >>>>
> > > >>>--
> > > >>>_______________________________________________ ____________
> > > >>>tw
> > > >>>
> > > >>>71 Bill Stroppe Baja Bronco
> > > >>>03 TJ Rubicon - Rubicon Express 4.5"
> > > >>>01 XJ Sport
> > > >>>
> > > >>>There is a very fine line between "hobby" and "mental illness."
> > > >>>-- Dave Barry
> > > >>>
> > > >>>Pronunciation: 'jEp
> > > >>>Function: noun
> > > >>>Date: 1940
> > > >>>
> > > >>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> > > >>>A small general-purpose motor vehicle with 80-inch wheelbase,
> > > >>>1/4-ton capacity, and four-wheel drive used by the U.S. army in
> > > >>>World War II.
> > > >>>
> > > >>>(Please remove the OBVIOUS to reply by email)
> > > >>>_______________________________________________ ____________
#154
Guest
Posts: n/a
Re: Black Diamond Suspension Lift Installed-questions
Exactly!
That shot shows it nice.
Here is a way you maybe able to see the physics while sitting at the
keyboard.
Take 2 pens and lay them on the table in front of you. Use your right
hand and grab the right end of the bottom pen with thumb and finger in a
pinch then put the second pen against the 1st finger's nail and hold it
there with the middle finger.
So you have thumb, pen, 1st finger, pen, middle finger which holds the
pens like the axle and control arm would fit on a rear end. Like
chopsticks but in reverse.
Then take the left hand and put your ring finger on the point of the top
pen which is where the t-case u-joint would be and grab the bottom pen
about 1/3 the way up which is where the frame mount is with the thumb
and 1st finger.
Then tilt the bottom pen down like the control arm would do.
The top pin's point will leave your left ring finger and draw away.
Mike
Peter Pontbriand wrote:
>
> If you look at this photo again
> http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG you'll see that the
> t-case yoke is forward of the frame end of the stock control arms for the
> rear axle. Same is true for the front, only even more pronounced.
>
> /Peter
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:4187DE1C.7CC24B10@sympatico.ca...
> > I could be mistaken, but I don't buy your explanation at all.
> >
> > The driveshaft pivot is up high on the t-case. The control arm front
> > pivot is low below the frame. The arc the lower arm describes will make
> > the driveshaft extend as it goes down.
> >
> > It is the lower arc's lower center that will draw the driveshaft out.
> >
> > I will look real close next time I see a TJ hoisted, that's for sure.
> > My curiosity is up.
> >
> > Mike
> >
> > Steve wrote:
> > >
> > > Hi Mike,
> > >
> > > Peter's right on that one. The TJ lower control arms are fixed to the
> > > frame between the t-case and axle. In other words, the radius of the
> > > control arm arc is shorter than the radius of the drive shaft arc. When
> > > the axle drops on the control arm arc, it gets closer to the t-case and
> > > compresses the drive shaft.
> > >
> > > By the way Peter, a lowered t-case will exaggerate the drive shaft
> > > compression but the shaft will compress even with the t-case cross
> > > member in the stock position.
> > >
> > > The upper arms pull the pinion angle down as the axle drops, so distance
> > > from pinion to t-case is increased a tiny bit, but this is relatively
> > > insignificant compared to the amount the distance is shortened as the
> > > axle drops on the lower control arm arc.
> > >
> > > My front shaft definitely compresses when the axle is hanging fully
> down.
> > >
> > > Steve
> > > http://xjeep.dyndns.org
> > >
> > > Mike Romain wrote:
> > > > The TJ has an upper and lower arm so the axle does indeed drop almost
> > > > straight down. The gent's photos show an upper control arm.
> > > >
> > > > I know the spring still sits flat at full droop because I have helped
> > > > replace them.
> > > >
> > > > Mike
> > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > 88 Cherokee 235 BFG AT's
> > > >
> > > > Peter Pontbriand wrote:
> > > >
> > > >>But, when the axle droops it doesn't drop straight down, it moves
> though an
> > > >>arc. The length of the control arms is fixed, so the whole axle
> assembly
> > > >>essentially pivots around the frame control arm mounts. Given that, if
> the
> > > >>transfer case output is lower than this pivot point, the driveshaft is
> going
> > > >>to compress.
> > > >>
> > > >>/Peter
> > > >>
> > > >>"twaldron" <thomas@OBVIOUSrubicons.com> wrote in message
> > > >>news:6pOhd.14801$bP2.8253@newssvr12.news.prodigy .com...
> > > >>
> > > >>>No. Your pumpkin end is lower than your xfer case end. If you droop
> the
> > > >>>axle, it moves further away from the xfer case output shaft and
> becomes
> > > >>>longer.
> > > >>>
> > > >>>Peter Pontbriand wrote:
> > > >>>
> > > >>>
> > > >>>>Full droop would shorten the drive shaft on a suspension like that,
> > > >>
> > > >>wouldn't
> > > >>
> > > >>>>it? I think the t-case output is lower than the frame-end control
> arm
> > > >>>>mounts. I'm pretty sure my drive shafts are compressed when the TJ
> is on
> > > >>
> > > >>a
> > > >>
> > > >>>>lift as compared to when it's sitting on it's wheels, even with the
> > > >>
> > > >>raised
> > > >>
> > > >>>>t-case skid.
> > > >>>>
> > > >>>>/Peter
> > > >>>>
> > > >>>>"Mike Romain" <romainm@sympatico.ca> wrote in message
> > > >>>>news:4187946D.85A9BF4B@sympatico.ca...
> > > >>>>
> > > >>>>
> > > >>>>>The oil spray is common for rust protection.
> > > >>>>>
> > > >>>>>Your rear pinion angle looks almost right from the angle the photo
> > > >>>>>shows. It is supposed to be pointing square at the driveshaft.
> > > >>>>>
> > > >>>>>If you jack up the rear of the Jeep and let the axle hang in space,
> it
> > > >>>>>can give you an idea if the axle is long enough. There is a spline
> slip
> > > >>>>>joint in the axle. If it is only say 1/4 the way out at full
> droop,
> > > >>>>>then likely you have tons of room to raise that plate back up where
> it
> > > >>>>>should be.
> > > >>>>>
> > > >>>>>While it's drooped you could at least unbolt the t-case end and
> just
> > > >>>>>hand place it up higher to see if it extends enough.
> > > >>>>>
> > > >>>>>Mike
> > > >>>>>
> > > >>>>>JimG wrote:
> > > >>>>>
> > > >>>>>
> > > >>>>>>No adjustable control arms:
> > > >>>>>>
> > > >>>>>>http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG
> > > >>>>>>http://www.citlink.net/~gunnoes/Photos/RearAxle.JPG
> > > >>>>>>
> > > >>>>>>Hey Mike... notice the oil sprayed under there? This Jeep was
> from
> > > >>>>>>Buffalo... the guy told me that was common practice in the north
> for
> > > >>>>
> > > >>>>rust
> > > >>>>
> > > >>>>
> > > >>>>>>prevention. Do they do that in Canada?
> > > >>>>>>
> > > >>>>>>JimG
> > > >>>>>>
> > > >>>>>>"twaldron" wrote in message ...
> > > >>>>>>
> > > >>>>>>
> > > >>>>>>>Here is my theory FWIW:
> > > >>>>>>>
> > > >>>>>>>The orig owner may have first passed on installing adj. control
> arms
> > > >>>>
> > > >>>>and
> > > >>>>
> > > >>>>
> > > >>>>>>>used the drop kit instead, thinking he was saving money. After
> > > >>>>>>>experiencing some driveline vibes even with the drop kit, he
> installed
> > > >>>>>>>the CV driveshaft. JimG might have to buy some adj. control arms
> to
> > > >>>>>>>complete the job. Of course, I'm going on one photo that does not
> show
> > > >>>>>>>everything (including a drop kit) and a vivid imagination.
> > > >>>>>>>
> > > >>>>>>>So what of it, JimG...do you have any adj. upper control arms?
> > > >>>>>>>
> > > >>>>
> > > >>>>
> > > >>>>
> > > >>>--
> > > >>>_______________________________________________ ____________
> > > >>>tw
> > > >>>
> > > >>>71 Bill Stroppe Baja Bronco
> > > >>>03 TJ Rubicon - Rubicon Express 4.5"
> > > >>>01 XJ Sport
> > > >>>
> > > >>>There is a very fine line between "hobby" and "mental illness."
> > > >>>-- Dave Barry
> > > >>>
> > > >>>Pronunciation: 'jEp
> > > >>>Function: noun
> > > >>>Date: 1940
> > > >>>
> > > >>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> > > >>>A small general-purpose motor vehicle with 80-inch wheelbase,
> > > >>>1/4-ton capacity, and four-wheel drive used by the U.S. army in
> > > >>>World War II.
> > > >>>
> > > >>>(Please remove the OBVIOUS to reply by email)
> > > >>>_______________________________________________ ____________
That shot shows it nice.
Here is a way you maybe able to see the physics while sitting at the
keyboard.
Take 2 pens and lay them on the table in front of you. Use your right
hand and grab the right end of the bottom pen with thumb and finger in a
pinch then put the second pen against the 1st finger's nail and hold it
there with the middle finger.
So you have thumb, pen, 1st finger, pen, middle finger which holds the
pens like the axle and control arm would fit on a rear end. Like
chopsticks but in reverse.
Then take the left hand and put your ring finger on the point of the top
pen which is where the t-case u-joint would be and grab the bottom pen
about 1/3 the way up which is where the frame mount is with the thumb
and 1st finger.
Then tilt the bottom pen down like the control arm would do.
The top pin's point will leave your left ring finger and draw away.
Mike
Peter Pontbriand wrote:
>
> If you look at this photo again
> http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG you'll see that the
> t-case yoke is forward of the frame end of the stock control arms for the
> rear axle. Same is true for the front, only even more pronounced.
>
> /Peter
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:4187DE1C.7CC24B10@sympatico.ca...
> > I could be mistaken, but I don't buy your explanation at all.
> >
> > The driveshaft pivot is up high on the t-case. The control arm front
> > pivot is low below the frame. The arc the lower arm describes will make
> > the driveshaft extend as it goes down.
> >
> > It is the lower arc's lower center that will draw the driveshaft out.
> >
> > I will look real close next time I see a TJ hoisted, that's for sure.
> > My curiosity is up.
> >
> > Mike
> >
> > Steve wrote:
> > >
> > > Hi Mike,
> > >
> > > Peter's right on that one. The TJ lower control arms are fixed to the
> > > frame between the t-case and axle. In other words, the radius of the
> > > control arm arc is shorter than the radius of the drive shaft arc. When
> > > the axle drops on the control arm arc, it gets closer to the t-case and
> > > compresses the drive shaft.
> > >
> > > By the way Peter, a lowered t-case will exaggerate the drive shaft
> > > compression but the shaft will compress even with the t-case cross
> > > member in the stock position.
> > >
> > > The upper arms pull the pinion angle down as the axle drops, so distance
> > > from pinion to t-case is increased a tiny bit, but this is relatively
> > > insignificant compared to the amount the distance is shortened as the
> > > axle drops on the lower control arm arc.
> > >
> > > My front shaft definitely compresses when the axle is hanging fully
> down.
> > >
> > > Steve
> > > http://xjeep.dyndns.org
> > >
> > > Mike Romain wrote:
> > > > The TJ has an upper and lower arm so the axle does indeed drop almost
> > > > straight down. The gent's photos show an upper control arm.
> > > >
> > > > I know the spring still sits flat at full droop because I have helped
> > > > replace them.
> > > >
> > > > Mike
> > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > 88 Cherokee 235 BFG AT's
> > > >
> > > > Peter Pontbriand wrote:
> > > >
> > > >>But, when the axle droops it doesn't drop straight down, it moves
> though an
> > > >>arc. The length of the control arms is fixed, so the whole axle
> assembly
> > > >>essentially pivots around the frame control arm mounts. Given that, if
> the
> > > >>transfer case output is lower than this pivot point, the driveshaft is
> going
> > > >>to compress.
> > > >>
> > > >>/Peter
> > > >>
> > > >>"twaldron" <thomas@OBVIOUSrubicons.com> wrote in message
> > > >>news:6pOhd.14801$bP2.8253@newssvr12.news.prodigy .com...
> > > >>
> > > >>>No. Your pumpkin end is lower than your xfer case end. If you droop
> the
> > > >>>axle, it moves further away from the xfer case output shaft and
> becomes
> > > >>>longer.
> > > >>>
> > > >>>Peter Pontbriand wrote:
> > > >>>
> > > >>>
> > > >>>>Full droop would shorten the drive shaft on a suspension like that,
> > > >>
> > > >>wouldn't
> > > >>
> > > >>>>it? I think the t-case output is lower than the frame-end control
> arm
> > > >>>>mounts. I'm pretty sure my drive shafts are compressed when the TJ
> is on
> > > >>
> > > >>a
> > > >>
> > > >>>>lift as compared to when it's sitting on it's wheels, even with the
> > > >>
> > > >>raised
> > > >>
> > > >>>>t-case skid.
> > > >>>>
> > > >>>>/Peter
> > > >>>>
> > > >>>>"Mike Romain" <romainm@sympatico.ca> wrote in message
> > > >>>>news:4187946D.85A9BF4B@sympatico.ca...
> > > >>>>
> > > >>>>
> > > >>>>>The oil spray is common for rust protection.
> > > >>>>>
> > > >>>>>Your rear pinion angle looks almost right from the angle the photo
> > > >>>>>shows. It is supposed to be pointing square at the driveshaft.
> > > >>>>>
> > > >>>>>If you jack up the rear of the Jeep and let the axle hang in space,
> it
> > > >>>>>can give you an idea if the axle is long enough. There is a spline
> slip
> > > >>>>>joint in the axle. If it is only say 1/4 the way out at full
> droop,
> > > >>>>>then likely you have tons of room to raise that plate back up where
> it
> > > >>>>>should be.
> > > >>>>>
> > > >>>>>While it's drooped you could at least unbolt the t-case end and
> just
> > > >>>>>hand place it up higher to see if it extends enough.
> > > >>>>>
> > > >>>>>Mike
> > > >>>>>
> > > >>>>>JimG wrote:
> > > >>>>>
> > > >>>>>
> > > >>>>>>No adjustable control arms:
> > > >>>>>>
> > > >>>>>>http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG
> > > >>>>>>http://www.citlink.net/~gunnoes/Photos/RearAxle.JPG
> > > >>>>>>
> > > >>>>>>Hey Mike... notice the oil sprayed under there? This Jeep was
> from
> > > >>>>>>Buffalo... the guy told me that was common practice in the north
> for
> > > >>>>
> > > >>>>rust
> > > >>>>
> > > >>>>
> > > >>>>>>prevention. Do they do that in Canada?
> > > >>>>>>
> > > >>>>>>JimG
> > > >>>>>>
> > > >>>>>>"twaldron" wrote in message ...
> > > >>>>>>
> > > >>>>>>
> > > >>>>>>>Here is my theory FWIW:
> > > >>>>>>>
> > > >>>>>>>The orig owner may have first passed on installing adj. control
> arms
> > > >>>>
> > > >>>>and
> > > >>>>
> > > >>>>
> > > >>>>>>>used the drop kit instead, thinking he was saving money. After
> > > >>>>>>>experiencing some driveline vibes even with the drop kit, he
> installed
> > > >>>>>>>the CV driveshaft. JimG might have to buy some adj. control arms
> to
> > > >>>>>>>complete the job. Of course, I'm going on one photo that does not
> show
> > > >>>>>>>everything (including a drop kit) and a vivid imagination.
> > > >>>>>>>
> > > >>>>>>>So what of it, JimG...do you have any adj. upper control arms?
> > > >>>>>>>
> > > >>>>
> > > >>>>
> > > >>>>
> > > >>>--
> > > >>>_______________________________________________ ____________
> > > >>>tw
> > > >>>
> > > >>>71 Bill Stroppe Baja Bronco
> > > >>>03 TJ Rubicon - Rubicon Express 4.5"
> > > >>>01 XJ Sport
> > > >>>
> > > >>>There is a very fine line between "hobby" and "mental illness."
> > > >>>-- Dave Barry
> > > >>>
> > > >>>Pronunciation: 'jEp
> > > >>>Function: noun
> > > >>>Date: 1940
> > > >>>
> > > >>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> > > >>>A small general-purpose motor vehicle with 80-inch wheelbase,
> > > >>>1/4-ton capacity, and four-wheel drive used by the U.S. army in
> > > >>>World War II.
> > > >>>
> > > >>>(Please remove the OBVIOUS to reply by email)
> > > >>>_______________________________________________ ____________
#155
Guest
Posts: n/a
Re: Black Diamond Suspension Lift Installed-questions
No need to fiddle with pens, all I have to do is go out in the garage,
measure the driveshaft length, jack up my TJ by the frame, and measure the
drive shaft length again to confirm that it compresses, not extends. I've
done this before, it's not theoretical, it's observable reality.
/Peter
"Mike Romain" <romainm@sympatico.ca> wrote in message
news:4187F694.BE316B40@sympatico.ca...
> Exactly!
>
> That shot shows it nice.
>
> Here is a way you maybe able to see the physics while sitting at the
> keyboard.
>
> Take 2 pens and lay them on the table in front of you. Use your right
> hand and grab the right end of the bottom pen with thumb and finger in a
> pinch then put the second pen against the 1st finger's nail and hold it
> there with the middle finger.
>
> So you have thumb, pen, 1st finger, pen, middle finger which holds the
> pens like the axle and control arm would fit on a rear end. Like
> chopsticks but in reverse.
>
> Then take the left hand and put your ring finger on the point of the top
> pen which is where the t-case u-joint would be and grab the bottom pen
> about 1/3 the way up which is where the frame mount is with the thumb
> and 1st finger.
>
> Then tilt the bottom pen down like the control arm would do.
>
> The top pin's point will leave your left ring finger and draw away.
>
> Mike
>
> Peter Pontbriand wrote:
> >
> > If you look at this photo again
> > http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG you'll see that the
> > t-case yoke is forward of the frame end of the stock control arms for
the
> > rear axle. Same is true for the front, only even more pronounced.
> >
> > /Peter
> >
> > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > news:4187DE1C.7CC24B10@sympatico.ca...
> > > I could be mistaken, but I don't buy your explanation at all.
> > >
> > > The driveshaft pivot is up high on the t-case. The control arm front
> > > pivot is low below the frame. The arc the lower arm describes will
make
> > > the driveshaft extend as it goes down.
> > >
> > > It is the lower arc's lower center that will draw the driveshaft out.
> > >
> > > I will look real close next time I see a TJ hoisted, that's for sure.
> > > My curiosity is up.
> > >
> > > Mike
> > >
> > > Steve wrote:
> > > >
> > > > Hi Mike,
> > > >
> > > > Peter's right on that one. The TJ lower control arms are fixed to
the
> > > > frame between the t-case and axle. In other words, the radius of the
> > > > control arm arc is shorter than the radius of the drive shaft arc.
When
> > > > the axle drops on the control arm arc, it gets closer to the t-case
and
> > > > compresses the drive shaft.
> > > >
> > > > By the way Peter, a lowered t-case will exaggerate the drive shaft
> > > > compression but the shaft will compress even with the t-case cross
> > > > member in the stock position.
> > > >
> > > > The upper arms pull the pinion angle down as the axle drops, so
distance
> > > > from pinion to t-case is increased a tiny bit, but this is
relatively
> > > > insignificant compared to the amount the distance is shortened as
the
> > > > axle drops on the lower control arm arc.
> > > >
> > > > My front shaft definitely compresses when the axle is hanging fully
> > down.
> > > >
> > > > Steve
> > > > http://xjeep.dyndns.org
> > > >
> > > > Mike Romain wrote:
> > > > > The TJ has an upper and lower arm so the axle does indeed drop
almost
> > > > > straight down. The gent's photos show an upper control arm.
> > > > >
> > > > > I know the spring still sits flat at full droop because I have
helped
> > > > > replace them.
> > > > >
> > > > > Mike
> > > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > > 88 Cherokee 235 BFG AT's
> > > > >
> > > > > Peter Pontbriand wrote:
> > > > >
> > > > >>But, when the axle droops it doesn't drop straight down, it moves
> > though an
> > > > >>arc. The length of the control arms is fixed, so the whole axle
> > assembly
> > > > >>essentially pivots around the frame control arm mounts. Given
that, if
> > the
> > > > >>transfer case output is lower than this pivot point, the
driveshaft is
> > going
> > > > >>to compress.
> > > > >>
> > > > >>/Peter
> > > > >>
> > > > >>"twaldron" <thomas@OBVIOUSrubicons.com> wrote in message
> > > > >>news:6pOhd.14801$bP2.8253@newssvr12.news.prodigy .com...
> > > > >>
> > > > >>>No. Your pumpkin end is lower than your xfer case end. If you
droop
> > the
> > > > >>>axle, it moves further away from the xfer case output shaft and
> > becomes
> > > > >>>longer.
> > > > >>>
> > > > >>>Peter Pontbriand wrote:
> > > > >>>
> > > > >>>
> > > > >>>>Full droop would shorten the drive shaft on a suspension like
that,
> > > > >>
> > > > >>wouldn't
> > > > >>
> > > > >>>>it? I think the t-case output is lower than the frame-end
control
> > arm
> > > > >>>>mounts. I'm pretty sure my drive shafts are compressed when the
TJ
> > is on
> > > > >>
> > > > >>a
> > > > >>
> > > > >>>>lift as compared to when it's sitting on it's wheels, even with
the
> > > > >>
> > > > >>raised
> > > > >>
> > > > >>>>t-case skid.
> > > > >>>>
> > > > >>>>/Peter
> > > > >>>>
> > > > >>>>"Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > >>>>news:4187946D.85A9BF4B@sympatico.ca...
> > > > >>>>
> > > > >>>>
> > > > >>>>>The oil spray is common for rust protection.
> > > > >>>>>
> > > > >>>>>Your rear pinion angle looks almost right from the angle the
photo
> > > > >>>>>shows. It is supposed to be pointing square at the driveshaft.
> > > > >>>>>
> > > > >>>>>If you jack up the rear of the Jeep and let the axle hang in
space,
> > it
> > > > >>>>>can give you an idea if the axle is long enough. There is a
spline
> > slip
> > > > >>>>>joint in the axle. If it is only say 1/4 the way out at full
> > droop,
> > > > >>>>>then likely you have tons of room to raise that plate back up
where
> > it
> > > > >>>>>should be.
> > > > >>>>>
> > > > >>>>>While it's drooped you could at least unbolt the t-case end and
> > just
> > > > >>>>>hand place it up higher to see if it extends enough.
> > > > >>>>>
> > > > >>>>>Mike
> > > > >>>>>
> > > > >>>>>JimG wrote:
> > > > >>>>>
> > > > >>>>>
> > > > >>>>>>No adjustable control arms:
> > > > >>>>>>
> > > > >>>>>>http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG
> > > > >>>>>>http://www.citlink.net/~gunnoes/Photos/RearAxle.JPG
> > > > >>>>>>
> > > > >>>>>>Hey Mike... notice the oil sprayed under there? This Jeep was
> > from
> > > > >>>>>>Buffalo... the guy told me that was common practice in the
north
> > for
> > > > >>>>
> > > > >>>>rust
> > > > >>>>
> > > > >>>>
> > > > >>>>>>prevention. Do they do that in Canada?
> > > > >>>>>>
> > > > >>>>>>JimG
> > > > >>>>>>
> > > > >>>>>>"twaldron" wrote in message ...
> > > > >>>>>>
> > > > >>>>>>
> > > > >>>>>>>Here is my theory FWIW:
> > > > >>>>>>>
> > > > >>>>>>>The orig owner may have first passed on installing adj.
control
> > arms
> > > > >>>>
> > > > >>>>and
> > > > >>>>
> > > > >>>>
> > > > >>>>>>>used the drop kit instead, thinking he was saving money.
After
> > > > >>>>>>>experiencing some driveline vibes even with the drop kit, he
> > installed
> > > > >>>>>>>the CV driveshaft. JimG might have to buy some adj. control
arms
> > to
> > > > >>>>>>>complete the job. Of course, I'm going on one photo that does
not
> > show
> > > > >>>>>>>everything (including a drop kit) and a vivid imagination.
> > > > >>>>>>>
> > > > >>>>>>>So what of it, JimG...do you have any adj. upper control
arms?
> > > > >>>>>>>
> > > > >>>>
> > > > >>>>
> > > > >>>>
> > > > >>>--
> > > > >>>_______________________________________________ ____________
> > > > >>>tw
> > > > >>>
> > > > >>>71 Bill Stroppe Baja Bronco
> > > > >>>03 TJ Rubicon - Rubicon Express 4.5"
> > > > >>>01 XJ Sport
> > > > >>>
> > > > >>>There is a very fine line between "hobby" and "mental illness."
> > > > >>>-- Dave Barry
> > > > >>>
> > > > >>>Pronunciation: 'jEp
> > > > >>>Function: noun
> > > > >>>Date: 1940
> > > > >>>
> > > > >>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> > > > >>>A small general-purpose motor vehicle with 80-inch wheelbase,
> > > > >>>1/4-ton capacity, and four-wheel drive used by the U.S. army in
> > > > >>>World War II.
> > > > >>>
> > > > >>>(Please remove the OBVIOUS to reply by email)
> > > > >>>_______________________________________________ ____________
measure the driveshaft length, jack up my TJ by the frame, and measure the
drive shaft length again to confirm that it compresses, not extends. I've
done this before, it's not theoretical, it's observable reality.
/Peter
"Mike Romain" <romainm@sympatico.ca> wrote in message
news:4187F694.BE316B40@sympatico.ca...
> Exactly!
>
> That shot shows it nice.
>
> Here is a way you maybe able to see the physics while sitting at the
> keyboard.
>
> Take 2 pens and lay them on the table in front of you. Use your right
> hand and grab the right end of the bottom pen with thumb and finger in a
> pinch then put the second pen against the 1st finger's nail and hold it
> there with the middle finger.
>
> So you have thumb, pen, 1st finger, pen, middle finger which holds the
> pens like the axle and control arm would fit on a rear end. Like
> chopsticks but in reverse.
>
> Then take the left hand and put your ring finger on the point of the top
> pen which is where the t-case u-joint would be and grab the bottom pen
> about 1/3 the way up which is where the frame mount is with the thumb
> and 1st finger.
>
> Then tilt the bottom pen down like the control arm would do.
>
> The top pin's point will leave your left ring finger and draw away.
>
> Mike
>
> Peter Pontbriand wrote:
> >
> > If you look at this photo again
> > http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG you'll see that the
> > t-case yoke is forward of the frame end of the stock control arms for
the
> > rear axle. Same is true for the front, only even more pronounced.
> >
> > /Peter
> >
> > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > news:4187DE1C.7CC24B10@sympatico.ca...
> > > I could be mistaken, but I don't buy your explanation at all.
> > >
> > > The driveshaft pivot is up high on the t-case. The control arm front
> > > pivot is low below the frame. The arc the lower arm describes will
make
> > > the driveshaft extend as it goes down.
> > >
> > > It is the lower arc's lower center that will draw the driveshaft out.
> > >
> > > I will look real close next time I see a TJ hoisted, that's for sure.
> > > My curiosity is up.
> > >
> > > Mike
> > >
> > > Steve wrote:
> > > >
> > > > Hi Mike,
> > > >
> > > > Peter's right on that one. The TJ lower control arms are fixed to
the
> > > > frame between the t-case and axle. In other words, the radius of the
> > > > control arm arc is shorter than the radius of the drive shaft arc.
When
> > > > the axle drops on the control arm arc, it gets closer to the t-case
and
> > > > compresses the drive shaft.
> > > >
> > > > By the way Peter, a lowered t-case will exaggerate the drive shaft
> > > > compression but the shaft will compress even with the t-case cross
> > > > member in the stock position.
> > > >
> > > > The upper arms pull the pinion angle down as the axle drops, so
distance
> > > > from pinion to t-case is increased a tiny bit, but this is
relatively
> > > > insignificant compared to the amount the distance is shortened as
the
> > > > axle drops on the lower control arm arc.
> > > >
> > > > My front shaft definitely compresses when the axle is hanging fully
> > down.
> > > >
> > > > Steve
> > > > http://xjeep.dyndns.org
> > > >
> > > > Mike Romain wrote:
> > > > > The TJ has an upper and lower arm so the axle does indeed drop
almost
> > > > > straight down. The gent's photos show an upper control arm.
> > > > >
> > > > > I know the spring still sits flat at full droop because I have
helped
> > > > > replace them.
> > > > >
> > > > > Mike
> > > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > > 88 Cherokee 235 BFG AT's
> > > > >
> > > > > Peter Pontbriand wrote:
> > > > >
> > > > >>But, when the axle droops it doesn't drop straight down, it moves
> > though an
> > > > >>arc. The length of the control arms is fixed, so the whole axle
> > assembly
> > > > >>essentially pivots around the frame control arm mounts. Given
that, if
> > the
> > > > >>transfer case output is lower than this pivot point, the
driveshaft is
> > going
> > > > >>to compress.
> > > > >>
> > > > >>/Peter
> > > > >>
> > > > >>"twaldron" <thomas@OBVIOUSrubicons.com> wrote in message
> > > > >>news:6pOhd.14801$bP2.8253@newssvr12.news.prodigy .com...
> > > > >>
> > > > >>>No. Your pumpkin end is lower than your xfer case end. If you
droop
> > the
> > > > >>>axle, it moves further away from the xfer case output shaft and
> > becomes
> > > > >>>longer.
> > > > >>>
> > > > >>>Peter Pontbriand wrote:
> > > > >>>
> > > > >>>
> > > > >>>>Full droop would shorten the drive shaft on a suspension like
that,
> > > > >>
> > > > >>wouldn't
> > > > >>
> > > > >>>>it? I think the t-case output is lower than the frame-end
control
> > arm
> > > > >>>>mounts. I'm pretty sure my drive shafts are compressed when the
TJ
> > is on
> > > > >>
> > > > >>a
> > > > >>
> > > > >>>>lift as compared to when it's sitting on it's wheels, even with
the
> > > > >>
> > > > >>raised
> > > > >>
> > > > >>>>t-case skid.
> > > > >>>>
> > > > >>>>/Peter
> > > > >>>>
> > > > >>>>"Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > >>>>news:4187946D.85A9BF4B@sympatico.ca...
> > > > >>>>
> > > > >>>>
> > > > >>>>>The oil spray is common for rust protection.
> > > > >>>>>
> > > > >>>>>Your rear pinion angle looks almost right from the angle the
photo
> > > > >>>>>shows. It is supposed to be pointing square at the driveshaft.
> > > > >>>>>
> > > > >>>>>If you jack up the rear of the Jeep and let the axle hang in
space,
> > it
> > > > >>>>>can give you an idea if the axle is long enough. There is a
spline
> > slip
> > > > >>>>>joint in the axle. If it is only say 1/4 the way out at full
> > droop,
> > > > >>>>>then likely you have tons of room to raise that plate back up
where
> > it
> > > > >>>>>should be.
> > > > >>>>>
> > > > >>>>>While it's drooped you could at least unbolt the t-case end and
> > just
> > > > >>>>>hand place it up higher to see if it extends enough.
> > > > >>>>>
> > > > >>>>>Mike
> > > > >>>>>
> > > > >>>>>JimG wrote:
> > > > >>>>>
> > > > >>>>>
> > > > >>>>>>No adjustable control arms:
> > > > >>>>>>
> > > > >>>>>>http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG
> > > > >>>>>>http://www.citlink.net/~gunnoes/Photos/RearAxle.JPG
> > > > >>>>>>
> > > > >>>>>>Hey Mike... notice the oil sprayed under there? This Jeep was
> > from
> > > > >>>>>>Buffalo... the guy told me that was common practice in the
north
> > for
> > > > >>>>
> > > > >>>>rust
> > > > >>>>
> > > > >>>>
> > > > >>>>>>prevention. Do they do that in Canada?
> > > > >>>>>>
> > > > >>>>>>JimG
> > > > >>>>>>
> > > > >>>>>>"twaldron" wrote in message ...
> > > > >>>>>>
> > > > >>>>>>
> > > > >>>>>>>Here is my theory FWIW:
> > > > >>>>>>>
> > > > >>>>>>>The orig owner may have first passed on installing adj.
control
> > arms
> > > > >>>>
> > > > >>>>and
> > > > >>>>
> > > > >>>>
> > > > >>>>>>>used the drop kit instead, thinking he was saving money.
After
> > > > >>>>>>>experiencing some driveline vibes even with the drop kit, he
> > installed
> > > > >>>>>>>the CV driveshaft. JimG might have to buy some adj. control
arms
> > to
> > > > >>>>>>>complete the job. Of course, I'm going on one photo that does
not
> > show
> > > > >>>>>>>everything (including a drop kit) and a vivid imagination.
> > > > >>>>>>>
> > > > >>>>>>>So what of it, JimG...do you have any adj. upper control
arms?
> > > > >>>>>>>
> > > > >>>>
> > > > >>>>
> > > > >>>>
> > > > >>>--
> > > > >>>_______________________________________________ ____________
> > > > >>>tw
> > > > >>>
> > > > >>>71 Bill Stroppe Baja Bronco
> > > > >>>03 TJ Rubicon - Rubicon Express 4.5"
> > > > >>>01 XJ Sport
> > > > >>>
> > > > >>>There is a very fine line between "hobby" and "mental illness."
> > > > >>>-- Dave Barry
> > > > >>>
> > > > >>>Pronunciation: 'jEp
> > > > >>>Function: noun
> > > > >>>Date: 1940
> > > > >>>
> > > > >>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> > > > >>>A small general-purpose motor vehicle with 80-inch wheelbase,
> > > > >>>1/4-ton capacity, and four-wheel drive used by the U.S. army in
> > > > >>>World War II.
> > > > >>>
> > > > >>>(Please remove the OBVIOUS to reply by email)
> > > > >>>_______________________________________________ ____________
#156
Guest
Posts: n/a
Re: Black Diamond Suspension Lift Installed-questions
No need to fiddle with pens, all I have to do is go out in the garage,
measure the driveshaft length, jack up my TJ by the frame, and measure the
drive shaft length again to confirm that it compresses, not extends. I've
done this before, it's not theoretical, it's observable reality.
/Peter
"Mike Romain" <romainm@sympatico.ca> wrote in message
news:4187F694.BE316B40@sympatico.ca...
> Exactly!
>
> That shot shows it nice.
>
> Here is a way you maybe able to see the physics while sitting at the
> keyboard.
>
> Take 2 pens and lay them on the table in front of you. Use your right
> hand and grab the right end of the bottom pen with thumb and finger in a
> pinch then put the second pen against the 1st finger's nail and hold it
> there with the middle finger.
>
> So you have thumb, pen, 1st finger, pen, middle finger which holds the
> pens like the axle and control arm would fit on a rear end. Like
> chopsticks but in reverse.
>
> Then take the left hand and put your ring finger on the point of the top
> pen which is where the t-case u-joint would be and grab the bottom pen
> about 1/3 the way up which is where the frame mount is with the thumb
> and 1st finger.
>
> Then tilt the bottom pen down like the control arm would do.
>
> The top pin's point will leave your left ring finger and draw away.
>
> Mike
>
> Peter Pontbriand wrote:
> >
> > If you look at this photo again
> > http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG you'll see that the
> > t-case yoke is forward of the frame end of the stock control arms for
the
> > rear axle. Same is true for the front, only even more pronounced.
> >
> > /Peter
> >
> > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > news:4187DE1C.7CC24B10@sympatico.ca...
> > > I could be mistaken, but I don't buy your explanation at all.
> > >
> > > The driveshaft pivot is up high on the t-case. The control arm front
> > > pivot is low below the frame. The arc the lower arm describes will
make
> > > the driveshaft extend as it goes down.
> > >
> > > It is the lower arc's lower center that will draw the driveshaft out.
> > >
> > > I will look real close next time I see a TJ hoisted, that's for sure.
> > > My curiosity is up.
> > >
> > > Mike
> > >
> > > Steve wrote:
> > > >
> > > > Hi Mike,
> > > >
> > > > Peter's right on that one. The TJ lower control arms are fixed to
the
> > > > frame between the t-case and axle. In other words, the radius of the
> > > > control arm arc is shorter than the radius of the drive shaft arc.
When
> > > > the axle drops on the control arm arc, it gets closer to the t-case
and
> > > > compresses the drive shaft.
> > > >
> > > > By the way Peter, a lowered t-case will exaggerate the drive shaft
> > > > compression but the shaft will compress even with the t-case cross
> > > > member in the stock position.
> > > >
> > > > The upper arms pull the pinion angle down as the axle drops, so
distance
> > > > from pinion to t-case is increased a tiny bit, but this is
relatively
> > > > insignificant compared to the amount the distance is shortened as
the
> > > > axle drops on the lower control arm arc.
> > > >
> > > > My front shaft definitely compresses when the axle is hanging fully
> > down.
> > > >
> > > > Steve
> > > > http://xjeep.dyndns.org
> > > >
> > > > Mike Romain wrote:
> > > > > The TJ has an upper and lower arm so the axle does indeed drop
almost
> > > > > straight down. The gent's photos show an upper control arm.
> > > > >
> > > > > I know the spring still sits flat at full droop because I have
helped
> > > > > replace them.
> > > > >
> > > > > Mike
> > > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > > 88 Cherokee 235 BFG AT's
> > > > >
> > > > > Peter Pontbriand wrote:
> > > > >
> > > > >>But, when the axle droops it doesn't drop straight down, it moves
> > though an
> > > > >>arc. The length of the control arms is fixed, so the whole axle
> > assembly
> > > > >>essentially pivots around the frame control arm mounts. Given
that, if
> > the
> > > > >>transfer case output is lower than this pivot point, the
driveshaft is
> > going
> > > > >>to compress.
> > > > >>
> > > > >>/Peter
> > > > >>
> > > > >>"twaldron" <thomas@OBVIOUSrubicons.com> wrote in message
> > > > >>news:6pOhd.14801$bP2.8253@newssvr12.news.prodigy .com...
> > > > >>
> > > > >>>No. Your pumpkin end is lower than your xfer case end. If you
droop
> > the
> > > > >>>axle, it moves further away from the xfer case output shaft and
> > becomes
> > > > >>>longer.
> > > > >>>
> > > > >>>Peter Pontbriand wrote:
> > > > >>>
> > > > >>>
> > > > >>>>Full droop would shorten the drive shaft on a suspension like
that,
> > > > >>
> > > > >>wouldn't
> > > > >>
> > > > >>>>it? I think the t-case output is lower than the frame-end
control
> > arm
> > > > >>>>mounts. I'm pretty sure my drive shafts are compressed when the
TJ
> > is on
> > > > >>
> > > > >>a
> > > > >>
> > > > >>>>lift as compared to when it's sitting on it's wheels, even with
the
> > > > >>
> > > > >>raised
> > > > >>
> > > > >>>>t-case skid.
> > > > >>>>
> > > > >>>>/Peter
> > > > >>>>
> > > > >>>>"Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > >>>>news:4187946D.85A9BF4B@sympatico.ca...
> > > > >>>>
> > > > >>>>
> > > > >>>>>The oil spray is common for rust protection.
> > > > >>>>>
> > > > >>>>>Your rear pinion angle looks almost right from the angle the
photo
> > > > >>>>>shows. It is supposed to be pointing square at the driveshaft.
> > > > >>>>>
> > > > >>>>>If you jack up the rear of the Jeep and let the axle hang in
space,
> > it
> > > > >>>>>can give you an idea if the axle is long enough. There is a
spline
> > slip
> > > > >>>>>joint in the axle. If it is only say 1/4 the way out at full
> > droop,
> > > > >>>>>then likely you have tons of room to raise that plate back up
where
> > it
> > > > >>>>>should be.
> > > > >>>>>
> > > > >>>>>While it's drooped you could at least unbolt the t-case end and
> > just
> > > > >>>>>hand place it up higher to see if it extends enough.
> > > > >>>>>
> > > > >>>>>Mike
> > > > >>>>>
> > > > >>>>>JimG wrote:
> > > > >>>>>
> > > > >>>>>
> > > > >>>>>>No adjustable control arms:
> > > > >>>>>>
> > > > >>>>>>http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG
> > > > >>>>>>http://www.citlink.net/~gunnoes/Photos/RearAxle.JPG
> > > > >>>>>>
> > > > >>>>>>Hey Mike... notice the oil sprayed under there? This Jeep was
> > from
> > > > >>>>>>Buffalo... the guy told me that was common practice in the
north
> > for
> > > > >>>>
> > > > >>>>rust
> > > > >>>>
> > > > >>>>
> > > > >>>>>>prevention. Do they do that in Canada?
> > > > >>>>>>
> > > > >>>>>>JimG
> > > > >>>>>>
> > > > >>>>>>"twaldron" wrote in message ...
> > > > >>>>>>
> > > > >>>>>>
> > > > >>>>>>>Here is my theory FWIW:
> > > > >>>>>>>
> > > > >>>>>>>The orig owner may have first passed on installing adj.
control
> > arms
> > > > >>>>
> > > > >>>>and
> > > > >>>>
> > > > >>>>
> > > > >>>>>>>used the drop kit instead, thinking he was saving money.
After
> > > > >>>>>>>experiencing some driveline vibes even with the drop kit, he
> > installed
> > > > >>>>>>>the CV driveshaft. JimG might have to buy some adj. control
arms
> > to
> > > > >>>>>>>complete the job. Of course, I'm going on one photo that does
not
> > show
> > > > >>>>>>>everything (including a drop kit) and a vivid imagination.
> > > > >>>>>>>
> > > > >>>>>>>So what of it, JimG...do you have any adj. upper control
arms?
> > > > >>>>>>>
> > > > >>>>
> > > > >>>>
> > > > >>>>
> > > > >>>--
> > > > >>>_______________________________________________ ____________
> > > > >>>tw
> > > > >>>
> > > > >>>71 Bill Stroppe Baja Bronco
> > > > >>>03 TJ Rubicon - Rubicon Express 4.5"
> > > > >>>01 XJ Sport
> > > > >>>
> > > > >>>There is a very fine line between "hobby" and "mental illness."
> > > > >>>-- Dave Barry
> > > > >>>
> > > > >>>Pronunciation: 'jEp
> > > > >>>Function: noun
> > > > >>>Date: 1940
> > > > >>>
> > > > >>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> > > > >>>A small general-purpose motor vehicle with 80-inch wheelbase,
> > > > >>>1/4-ton capacity, and four-wheel drive used by the U.S. army in
> > > > >>>World War II.
> > > > >>>
> > > > >>>(Please remove the OBVIOUS to reply by email)
> > > > >>>_______________________________________________ ____________
measure the driveshaft length, jack up my TJ by the frame, and measure the
drive shaft length again to confirm that it compresses, not extends. I've
done this before, it's not theoretical, it's observable reality.
/Peter
"Mike Romain" <romainm@sympatico.ca> wrote in message
news:4187F694.BE316B40@sympatico.ca...
> Exactly!
>
> That shot shows it nice.
>
> Here is a way you maybe able to see the physics while sitting at the
> keyboard.
>
> Take 2 pens and lay them on the table in front of you. Use your right
> hand and grab the right end of the bottom pen with thumb and finger in a
> pinch then put the second pen against the 1st finger's nail and hold it
> there with the middle finger.
>
> So you have thumb, pen, 1st finger, pen, middle finger which holds the
> pens like the axle and control arm would fit on a rear end. Like
> chopsticks but in reverse.
>
> Then take the left hand and put your ring finger on the point of the top
> pen which is where the t-case u-joint would be and grab the bottom pen
> about 1/3 the way up which is where the frame mount is with the thumb
> and 1st finger.
>
> Then tilt the bottom pen down like the control arm would do.
>
> The top pin's point will leave your left ring finger and draw away.
>
> Mike
>
> Peter Pontbriand wrote:
> >
> > If you look at this photo again
> > http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG you'll see that the
> > t-case yoke is forward of the frame end of the stock control arms for
the
> > rear axle. Same is true for the front, only even more pronounced.
> >
> > /Peter
> >
> > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > news:4187DE1C.7CC24B10@sympatico.ca...
> > > I could be mistaken, but I don't buy your explanation at all.
> > >
> > > The driveshaft pivot is up high on the t-case. The control arm front
> > > pivot is low below the frame. The arc the lower arm describes will
make
> > > the driveshaft extend as it goes down.
> > >
> > > It is the lower arc's lower center that will draw the driveshaft out.
> > >
> > > I will look real close next time I see a TJ hoisted, that's for sure.
> > > My curiosity is up.
> > >
> > > Mike
> > >
> > > Steve wrote:
> > > >
> > > > Hi Mike,
> > > >
> > > > Peter's right on that one. The TJ lower control arms are fixed to
the
> > > > frame between the t-case and axle. In other words, the radius of the
> > > > control arm arc is shorter than the radius of the drive shaft arc.
When
> > > > the axle drops on the control arm arc, it gets closer to the t-case
and
> > > > compresses the drive shaft.
> > > >
> > > > By the way Peter, a lowered t-case will exaggerate the drive shaft
> > > > compression but the shaft will compress even with the t-case cross
> > > > member in the stock position.
> > > >
> > > > The upper arms pull the pinion angle down as the axle drops, so
distance
> > > > from pinion to t-case is increased a tiny bit, but this is
relatively
> > > > insignificant compared to the amount the distance is shortened as
the
> > > > axle drops on the lower control arm arc.
> > > >
> > > > My front shaft definitely compresses when the axle is hanging fully
> > down.
> > > >
> > > > Steve
> > > > http://xjeep.dyndns.org
> > > >
> > > > Mike Romain wrote:
> > > > > The TJ has an upper and lower arm so the axle does indeed drop
almost
> > > > > straight down. The gent's photos show an upper control arm.
> > > > >
> > > > > I know the spring still sits flat at full droop because I have
helped
> > > > > replace them.
> > > > >
> > > > > Mike
> > > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > > 88 Cherokee 235 BFG AT's
> > > > >
> > > > > Peter Pontbriand wrote:
> > > > >
> > > > >>But, when the axle droops it doesn't drop straight down, it moves
> > though an
> > > > >>arc. The length of the control arms is fixed, so the whole axle
> > assembly
> > > > >>essentially pivots around the frame control arm mounts. Given
that, if
> > the
> > > > >>transfer case output is lower than this pivot point, the
driveshaft is
> > going
> > > > >>to compress.
> > > > >>
> > > > >>/Peter
> > > > >>
> > > > >>"twaldron" <thomas@OBVIOUSrubicons.com> wrote in message
> > > > >>news:6pOhd.14801$bP2.8253@newssvr12.news.prodigy .com...
> > > > >>
> > > > >>>No. Your pumpkin end is lower than your xfer case end. If you
droop
> > the
> > > > >>>axle, it moves further away from the xfer case output shaft and
> > becomes
> > > > >>>longer.
> > > > >>>
> > > > >>>Peter Pontbriand wrote:
> > > > >>>
> > > > >>>
> > > > >>>>Full droop would shorten the drive shaft on a suspension like
that,
> > > > >>
> > > > >>wouldn't
> > > > >>
> > > > >>>>it? I think the t-case output is lower than the frame-end
control
> > arm
> > > > >>>>mounts. I'm pretty sure my drive shafts are compressed when the
TJ
> > is on
> > > > >>
> > > > >>a
> > > > >>
> > > > >>>>lift as compared to when it's sitting on it's wheels, even with
the
> > > > >>
> > > > >>raised
> > > > >>
> > > > >>>>t-case skid.
> > > > >>>>
> > > > >>>>/Peter
> > > > >>>>
> > > > >>>>"Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > >>>>news:4187946D.85A9BF4B@sympatico.ca...
> > > > >>>>
> > > > >>>>
> > > > >>>>>The oil spray is common for rust protection.
> > > > >>>>>
> > > > >>>>>Your rear pinion angle looks almost right from the angle the
photo
> > > > >>>>>shows. It is supposed to be pointing square at the driveshaft.
> > > > >>>>>
> > > > >>>>>If you jack up the rear of the Jeep and let the axle hang in
space,
> > it
> > > > >>>>>can give you an idea if the axle is long enough. There is a
spline
> > slip
> > > > >>>>>joint in the axle. If it is only say 1/4 the way out at full
> > droop,
> > > > >>>>>then likely you have tons of room to raise that plate back up
where
> > it
> > > > >>>>>should be.
> > > > >>>>>
> > > > >>>>>While it's drooped you could at least unbolt the t-case end and
> > just
> > > > >>>>>hand place it up higher to see if it extends enough.
> > > > >>>>>
> > > > >>>>>Mike
> > > > >>>>>
> > > > >>>>>JimG wrote:
> > > > >>>>>
> > > > >>>>>
> > > > >>>>>>No adjustable control arms:
> > > > >>>>>>
> > > > >>>>>>http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG
> > > > >>>>>>http://www.citlink.net/~gunnoes/Photos/RearAxle.JPG
> > > > >>>>>>
> > > > >>>>>>Hey Mike... notice the oil sprayed under there? This Jeep was
> > from
> > > > >>>>>>Buffalo... the guy told me that was common practice in the
north
> > for
> > > > >>>>
> > > > >>>>rust
> > > > >>>>
> > > > >>>>
> > > > >>>>>>prevention. Do they do that in Canada?
> > > > >>>>>>
> > > > >>>>>>JimG
> > > > >>>>>>
> > > > >>>>>>"twaldron" wrote in message ...
> > > > >>>>>>
> > > > >>>>>>
> > > > >>>>>>>Here is my theory FWIW:
> > > > >>>>>>>
> > > > >>>>>>>The orig owner may have first passed on installing adj.
control
> > arms
> > > > >>>>
> > > > >>>>and
> > > > >>>>
> > > > >>>>
> > > > >>>>>>>used the drop kit instead, thinking he was saving money.
After
> > > > >>>>>>>experiencing some driveline vibes even with the drop kit, he
> > installed
> > > > >>>>>>>the CV driveshaft. JimG might have to buy some adj. control
arms
> > to
> > > > >>>>>>>complete the job. Of course, I'm going on one photo that does
not
> > show
> > > > >>>>>>>everything (including a drop kit) and a vivid imagination.
> > > > >>>>>>>
> > > > >>>>>>>So what of it, JimG...do you have any adj. upper control
arms?
> > > > >>>>>>>
> > > > >>>>
> > > > >>>>
> > > > >>>>
> > > > >>>--
> > > > >>>_______________________________________________ ____________
> > > > >>>tw
> > > > >>>
> > > > >>>71 Bill Stroppe Baja Bronco
> > > > >>>03 TJ Rubicon - Rubicon Express 4.5"
> > > > >>>01 XJ Sport
> > > > >>>
> > > > >>>There is a very fine line between "hobby" and "mental illness."
> > > > >>>-- Dave Barry
> > > > >>>
> > > > >>>Pronunciation: 'jEp
> > > > >>>Function: noun
> > > > >>>Date: 1940
> > > > >>>
> > > > >>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> > > > >>>A small general-purpose motor vehicle with 80-inch wheelbase,
> > > > >>>1/4-ton capacity, and four-wheel drive used by the U.S. army in
> > > > >>>World War II.
> > > > >>>
> > > > >>>(Please remove the OBVIOUS to reply by email)
> > > > >>>_______________________________________________ ____________
#157
Guest
Posts: n/a
Re: Black Diamond Suspension Lift Installed-questions
No need to fiddle with pens, all I have to do is go out in the garage,
measure the driveshaft length, jack up my TJ by the frame, and measure the
drive shaft length again to confirm that it compresses, not extends. I've
done this before, it's not theoretical, it's observable reality.
/Peter
"Mike Romain" <romainm@sympatico.ca> wrote in message
news:4187F694.BE316B40@sympatico.ca...
> Exactly!
>
> That shot shows it nice.
>
> Here is a way you maybe able to see the physics while sitting at the
> keyboard.
>
> Take 2 pens and lay them on the table in front of you. Use your right
> hand and grab the right end of the bottom pen with thumb and finger in a
> pinch then put the second pen against the 1st finger's nail and hold it
> there with the middle finger.
>
> So you have thumb, pen, 1st finger, pen, middle finger which holds the
> pens like the axle and control arm would fit on a rear end. Like
> chopsticks but in reverse.
>
> Then take the left hand and put your ring finger on the point of the top
> pen which is where the t-case u-joint would be and grab the bottom pen
> about 1/3 the way up which is where the frame mount is with the thumb
> and 1st finger.
>
> Then tilt the bottom pen down like the control arm would do.
>
> The top pin's point will leave your left ring finger and draw away.
>
> Mike
>
> Peter Pontbriand wrote:
> >
> > If you look at this photo again
> > http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG you'll see that the
> > t-case yoke is forward of the frame end of the stock control arms for
the
> > rear axle. Same is true for the front, only even more pronounced.
> >
> > /Peter
> >
> > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > news:4187DE1C.7CC24B10@sympatico.ca...
> > > I could be mistaken, but I don't buy your explanation at all.
> > >
> > > The driveshaft pivot is up high on the t-case. The control arm front
> > > pivot is low below the frame. The arc the lower arm describes will
make
> > > the driveshaft extend as it goes down.
> > >
> > > It is the lower arc's lower center that will draw the driveshaft out.
> > >
> > > I will look real close next time I see a TJ hoisted, that's for sure.
> > > My curiosity is up.
> > >
> > > Mike
> > >
> > > Steve wrote:
> > > >
> > > > Hi Mike,
> > > >
> > > > Peter's right on that one. The TJ lower control arms are fixed to
the
> > > > frame between the t-case and axle. In other words, the radius of the
> > > > control arm arc is shorter than the radius of the drive shaft arc.
When
> > > > the axle drops on the control arm arc, it gets closer to the t-case
and
> > > > compresses the drive shaft.
> > > >
> > > > By the way Peter, a lowered t-case will exaggerate the drive shaft
> > > > compression but the shaft will compress even with the t-case cross
> > > > member in the stock position.
> > > >
> > > > The upper arms pull the pinion angle down as the axle drops, so
distance
> > > > from pinion to t-case is increased a tiny bit, but this is
relatively
> > > > insignificant compared to the amount the distance is shortened as
the
> > > > axle drops on the lower control arm arc.
> > > >
> > > > My front shaft definitely compresses when the axle is hanging fully
> > down.
> > > >
> > > > Steve
> > > > http://xjeep.dyndns.org
> > > >
> > > > Mike Romain wrote:
> > > > > The TJ has an upper and lower arm so the axle does indeed drop
almost
> > > > > straight down. The gent's photos show an upper control arm.
> > > > >
> > > > > I know the spring still sits flat at full droop because I have
helped
> > > > > replace them.
> > > > >
> > > > > Mike
> > > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > > 88 Cherokee 235 BFG AT's
> > > > >
> > > > > Peter Pontbriand wrote:
> > > > >
> > > > >>But, when the axle droops it doesn't drop straight down, it moves
> > though an
> > > > >>arc. The length of the control arms is fixed, so the whole axle
> > assembly
> > > > >>essentially pivots around the frame control arm mounts. Given
that, if
> > the
> > > > >>transfer case output is lower than this pivot point, the
driveshaft is
> > going
> > > > >>to compress.
> > > > >>
> > > > >>/Peter
> > > > >>
> > > > >>"twaldron" <thomas@OBVIOUSrubicons.com> wrote in message
> > > > >>news:6pOhd.14801$bP2.8253@newssvr12.news.prodigy .com...
> > > > >>
> > > > >>>No. Your pumpkin end is lower than your xfer case end. If you
droop
> > the
> > > > >>>axle, it moves further away from the xfer case output shaft and
> > becomes
> > > > >>>longer.
> > > > >>>
> > > > >>>Peter Pontbriand wrote:
> > > > >>>
> > > > >>>
> > > > >>>>Full droop would shorten the drive shaft on a suspension like
that,
> > > > >>
> > > > >>wouldn't
> > > > >>
> > > > >>>>it? I think the t-case output is lower than the frame-end
control
> > arm
> > > > >>>>mounts. I'm pretty sure my drive shafts are compressed when the
TJ
> > is on
> > > > >>
> > > > >>a
> > > > >>
> > > > >>>>lift as compared to when it's sitting on it's wheels, even with
the
> > > > >>
> > > > >>raised
> > > > >>
> > > > >>>>t-case skid.
> > > > >>>>
> > > > >>>>/Peter
> > > > >>>>
> > > > >>>>"Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > >>>>news:4187946D.85A9BF4B@sympatico.ca...
> > > > >>>>
> > > > >>>>
> > > > >>>>>The oil spray is common for rust protection.
> > > > >>>>>
> > > > >>>>>Your rear pinion angle looks almost right from the angle the
photo
> > > > >>>>>shows. It is supposed to be pointing square at the driveshaft.
> > > > >>>>>
> > > > >>>>>If you jack up the rear of the Jeep and let the axle hang in
space,
> > it
> > > > >>>>>can give you an idea if the axle is long enough. There is a
spline
> > slip
> > > > >>>>>joint in the axle. If it is only say 1/4 the way out at full
> > droop,
> > > > >>>>>then likely you have tons of room to raise that plate back up
where
> > it
> > > > >>>>>should be.
> > > > >>>>>
> > > > >>>>>While it's drooped you could at least unbolt the t-case end and
> > just
> > > > >>>>>hand place it up higher to see if it extends enough.
> > > > >>>>>
> > > > >>>>>Mike
> > > > >>>>>
> > > > >>>>>JimG wrote:
> > > > >>>>>
> > > > >>>>>
> > > > >>>>>>No adjustable control arms:
> > > > >>>>>>
> > > > >>>>>>http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG
> > > > >>>>>>http://www.citlink.net/~gunnoes/Photos/RearAxle.JPG
> > > > >>>>>>
> > > > >>>>>>Hey Mike... notice the oil sprayed under there? This Jeep was
> > from
> > > > >>>>>>Buffalo... the guy told me that was common practice in the
north
> > for
> > > > >>>>
> > > > >>>>rust
> > > > >>>>
> > > > >>>>
> > > > >>>>>>prevention. Do they do that in Canada?
> > > > >>>>>>
> > > > >>>>>>JimG
> > > > >>>>>>
> > > > >>>>>>"twaldron" wrote in message ...
> > > > >>>>>>
> > > > >>>>>>
> > > > >>>>>>>Here is my theory FWIW:
> > > > >>>>>>>
> > > > >>>>>>>The orig owner may have first passed on installing adj.
control
> > arms
> > > > >>>>
> > > > >>>>and
> > > > >>>>
> > > > >>>>
> > > > >>>>>>>used the drop kit instead, thinking he was saving money.
After
> > > > >>>>>>>experiencing some driveline vibes even with the drop kit, he
> > installed
> > > > >>>>>>>the CV driveshaft. JimG might have to buy some adj. control
arms
> > to
> > > > >>>>>>>complete the job. Of course, I'm going on one photo that does
not
> > show
> > > > >>>>>>>everything (including a drop kit) and a vivid imagination.
> > > > >>>>>>>
> > > > >>>>>>>So what of it, JimG...do you have any adj. upper control
arms?
> > > > >>>>>>>
> > > > >>>>
> > > > >>>>
> > > > >>>>
> > > > >>>--
> > > > >>>_______________________________________________ ____________
> > > > >>>tw
> > > > >>>
> > > > >>>71 Bill Stroppe Baja Bronco
> > > > >>>03 TJ Rubicon - Rubicon Express 4.5"
> > > > >>>01 XJ Sport
> > > > >>>
> > > > >>>There is a very fine line between "hobby" and "mental illness."
> > > > >>>-- Dave Barry
> > > > >>>
> > > > >>>Pronunciation: 'jEp
> > > > >>>Function: noun
> > > > >>>Date: 1940
> > > > >>>
> > > > >>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> > > > >>>A small general-purpose motor vehicle with 80-inch wheelbase,
> > > > >>>1/4-ton capacity, and four-wheel drive used by the U.S. army in
> > > > >>>World War II.
> > > > >>>
> > > > >>>(Please remove the OBVIOUS to reply by email)
> > > > >>>_______________________________________________ ____________
measure the driveshaft length, jack up my TJ by the frame, and measure the
drive shaft length again to confirm that it compresses, not extends. I've
done this before, it's not theoretical, it's observable reality.
/Peter
"Mike Romain" <romainm@sympatico.ca> wrote in message
news:4187F694.BE316B40@sympatico.ca...
> Exactly!
>
> That shot shows it nice.
>
> Here is a way you maybe able to see the physics while sitting at the
> keyboard.
>
> Take 2 pens and lay them on the table in front of you. Use your right
> hand and grab the right end of the bottom pen with thumb and finger in a
> pinch then put the second pen against the 1st finger's nail and hold it
> there with the middle finger.
>
> So you have thumb, pen, 1st finger, pen, middle finger which holds the
> pens like the axle and control arm would fit on a rear end. Like
> chopsticks but in reverse.
>
> Then take the left hand and put your ring finger on the point of the top
> pen which is where the t-case u-joint would be and grab the bottom pen
> about 1/3 the way up which is where the frame mount is with the thumb
> and 1st finger.
>
> Then tilt the bottom pen down like the control arm would do.
>
> The top pin's point will leave your left ring finger and draw away.
>
> Mike
>
> Peter Pontbriand wrote:
> >
> > If you look at this photo again
> > http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG you'll see that the
> > t-case yoke is forward of the frame end of the stock control arms for
the
> > rear axle. Same is true for the front, only even more pronounced.
> >
> > /Peter
> >
> > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > news:4187DE1C.7CC24B10@sympatico.ca...
> > > I could be mistaken, but I don't buy your explanation at all.
> > >
> > > The driveshaft pivot is up high on the t-case. The control arm front
> > > pivot is low below the frame. The arc the lower arm describes will
make
> > > the driveshaft extend as it goes down.
> > >
> > > It is the lower arc's lower center that will draw the driveshaft out.
> > >
> > > I will look real close next time I see a TJ hoisted, that's for sure.
> > > My curiosity is up.
> > >
> > > Mike
> > >
> > > Steve wrote:
> > > >
> > > > Hi Mike,
> > > >
> > > > Peter's right on that one. The TJ lower control arms are fixed to
the
> > > > frame between the t-case and axle. In other words, the radius of the
> > > > control arm arc is shorter than the radius of the drive shaft arc.
When
> > > > the axle drops on the control arm arc, it gets closer to the t-case
and
> > > > compresses the drive shaft.
> > > >
> > > > By the way Peter, a lowered t-case will exaggerate the drive shaft
> > > > compression but the shaft will compress even with the t-case cross
> > > > member in the stock position.
> > > >
> > > > The upper arms pull the pinion angle down as the axle drops, so
distance
> > > > from pinion to t-case is increased a tiny bit, but this is
relatively
> > > > insignificant compared to the amount the distance is shortened as
the
> > > > axle drops on the lower control arm arc.
> > > >
> > > > My front shaft definitely compresses when the axle is hanging fully
> > down.
> > > >
> > > > Steve
> > > > http://xjeep.dyndns.org
> > > >
> > > > Mike Romain wrote:
> > > > > The TJ has an upper and lower arm so the axle does indeed drop
almost
> > > > > straight down. The gent's photos show an upper control arm.
> > > > >
> > > > > I know the spring still sits flat at full droop because I have
helped
> > > > > replace them.
> > > > >
> > > > > Mike
> > > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > > 88 Cherokee 235 BFG AT's
> > > > >
> > > > > Peter Pontbriand wrote:
> > > > >
> > > > >>But, when the axle droops it doesn't drop straight down, it moves
> > though an
> > > > >>arc. The length of the control arms is fixed, so the whole axle
> > assembly
> > > > >>essentially pivots around the frame control arm mounts. Given
that, if
> > the
> > > > >>transfer case output is lower than this pivot point, the
driveshaft is
> > going
> > > > >>to compress.
> > > > >>
> > > > >>/Peter
> > > > >>
> > > > >>"twaldron" <thomas@OBVIOUSrubicons.com> wrote in message
> > > > >>news:6pOhd.14801$bP2.8253@newssvr12.news.prodigy .com...
> > > > >>
> > > > >>>No. Your pumpkin end is lower than your xfer case end. If you
droop
> > the
> > > > >>>axle, it moves further away from the xfer case output shaft and
> > becomes
> > > > >>>longer.
> > > > >>>
> > > > >>>Peter Pontbriand wrote:
> > > > >>>
> > > > >>>
> > > > >>>>Full droop would shorten the drive shaft on a suspension like
that,
> > > > >>
> > > > >>wouldn't
> > > > >>
> > > > >>>>it? I think the t-case output is lower than the frame-end
control
> > arm
> > > > >>>>mounts. I'm pretty sure my drive shafts are compressed when the
TJ
> > is on
> > > > >>
> > > > >>a
> > > > >>
> > > > >>>>lift as compared to when it's sitting on it's wheels, even with
the
> > > > >>
> > > > >>raised
> > > > >>
> > > > >>>>t-case skid.
> > > > >>>>
> > > > >>>>/Peter
> > > > >>>>
> > > > >>>>"Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > >>>>news:4187946D.85A9BF4B@sympatico.ca...
> > > > >>>>
> > > > >>>>
> > > > >>>>>The oil spray is common for rust protection.
> > > > >>>>>
> > > > >>>>>Your rear pinion angle looks almost right from the angle the
photo
> > > > >>>>>shows. It is supposed to be pointing square at the driveshaft.
> > > > >>>>>
> > > > >>>>>If you jack up the rear of the Jeep and let the axle hang in
space,
> > it
> > > > >>>>>can give you an idea if the axle is long enough. There is a
spline
> > slip
> > > > >>>>>joint in the axle. If it is only say 1/4 the way out at full
> > droop,
> > > > >>>>>then likely you have tons of room to raise that plate back up
where
> > it
> > > > >>>>>should be.
> > > > >>>>>
> > > > >>>>>While it's drooped you could at least unbolt the t-case end and
> > just
> > > > >>>>>hand place it up higher to see if it extends enough.
> > > > >>>>>
> > > > >>>>>Mike
> > > > >>>>>
> > > > >>>>>JimG wrote:
> > > > >>>>>
> > > > >>>>>
> > > > >>>>>>No adjustable control arms:
> > > > >>>>>>
> > > > >>>>>>http://www.citlink.net/~gunnoes/Photos/LowerKit.JPG
> > > > >>>>>>http://www.citlink.net/~gunnoes/Photos/RearAxle.JPG
> > > > >>>>>>
> > > > >>>>>>Hey Mike... notice the oil sprayed under there? This Jeep was
> > from
> > > > >>>>>>Buffalo... the guy told me that was common practice in the
north
> > for
> > > > >>>>
> > > > >>>>rust
> > > > >>>>
> > > > >>>>
> > > > >>>>>>prevention. Do they do that in Canada?
> > > > >>>>>>
> > > > >>>>>>JimG
> > > > >>>>>>
> > > > >>>>>>"twaldron" wrote in message ...
> > > > >>>>>>
> > > > >>>>>>
> > > > >>>>>>>Here is my theory FWIW:
> > > > >>>>>>>
> > > > >>>>>>>The orig owner may have first passed on installing adj.
control
> > arms
> > > > >>>>
> > > > >>>>and
> > > > >>>>
> > > > >>>>
> > > > >>>>>>>used the drop kit instead, thinking he was saving money.
After
> > > > >>>>>>>experiencing some driveline vibes even with the drop kit, he
> > installed
> > > > >>>>>>>the CV driveshaft. JimG might have to buy some adj. control
arms
> > to
> > > > >>>>>>>complete the job. Of course, I'm going on one photo that does
not
> > show
> > > > >>>>>>>everything (including a drop kit) and a vivid imagination.
> > > > >>>>>>>
> > > > >>>>>>>So what of it, JimG...do you have any adj. upper control
arms?
> > > > >>>>>>>
> > > > >>>>
> > > > >>>>
> > > > >>>>
> > > > >>>--
> > > > >>>_______________________________________________ ____________
> > > > >>>tw
> > > > >>>
> > > > >>>71 Bill Stroppe Baja Bronco
> > > > >>>03 TJ Rubicon - Rubicon Express 4.5"
> > > > >>>01 XJ Sport
> > > > >>>
> > > > >>>There is a very fine line between "hobby" and "mental illness."
> > > > >>>-- Dave Barry
> > > > >>>
> > > > >>>Pronunciation: 'jEp
> > > > >>>Function: noun
> > > > >>>Date: 1940
> > > > >>>
> > > > >>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> > > > >>>A small general-purpose motor vehicle with 80-inch wheelbase,
> > > > >>>1/4-ton capacity, and four-wheel drive used by the U.S. army in
> > > > >>>World War II.
> > > > >>>
> > > > >>>(Please remove the OBVIOUS to reply by email)
> > > > >>>_______________________________________________ ____________
#158
Guest
Posts: n/a
Re: Black Diamond Suspension Lift Installed-questions
Oh, go ahead and throw reality into this!!!!!!
Peter Pontbriand wrote:
> No need to fiddle with pens, all I have to do is go out in the garage,
> measure the driveshaft length, jack up my TJ by the frame, and measure the
> drive shaft length again to confirm that it compresses, not extends. I've
> done this before, it's not theoretical, it's observable reality.
>
> /Peter
--
__________________________________________________ _________
tw
71 Bill Stroppe Baja Bronco
03 TJ Rubicon - Rubicon Express 4.5"
01 XJ Sport
There is a very fine line between "hobby" and "mental illness."
-- Dave Barry
Pronunciation: 'jEp
Function: noun
Date: 1940
Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
A small general-purpose motor vehicle with 80-inch wheelbase,
1/4-ton capacity, and four-wheel drive used by the U.S. army in
World War II.
(Please remove the OBVIOUS to reply by email)
__________________________________________________ _________
Peter Pontbriand wrote:
> No need to fiddle with pens, all I have to do is go out in the garage,
> measure the driveshaft length, jack up my TJ by the frame, and measure the
> drive shaft length again to confirm that it compresses, not extends. I've
> done this before, it's not theoretical, it's observable reality.
>
> /Peter
--
__________________________________________________ _________
tw
71 Bill Stroppe Baja Bronco
03 TJ Rubicon - Rubicon Express 4.5"
01 XJ Sport
There is a very fine line between "hobby" and "mental illness."
-- Dave Barry
Pronunciation: 'jEp
Function: noun
Date: 1940
Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
A small general-purpose motor vehicle with 80-inch wheelbase,
1/4-ton capacity, and four-wheel drive used by the U.S. army in
World War II.
(Please remove the OBVIOUS to reply by email)
__________________________________________________ _________
#159
Guest
Posts: n/a
Re: Black Diamond Suspension Lift Installed-questions
Oh, go ahead and throw reality into this!!!!!!
Peter Pontbriand wrote:
> No need to fiddle with pens, all I have to do is go out in the garage,
> measure the driveshaft length, jack up my TJ by the frame, and measure the
> drive shaft length again to confirm that it compresses, not extends. I've
> done this before, it's not theoretical, it's observable reality.
>
> /Peter
--
__________________________________________________ _________
tw
71 Bill Stroppe Baja Bronco
03 TJ Rubicon - Rubicon Express 4.5"
01 XJ Sport
There is a very fine line between "hobby" and "mental illness."
-- Dave Barry
Pronunciation: 'jEp
Function: noun
Date: 1940
Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
A small general-purpose motor vehicle with 80-inch wheelbase,
1/4-ton capacity, and four-wheel drive used by the U.S. army in
World War II.
(Please remove the OBVIOUS to reply by email)
__________________________________________________ _________
Peter Pontbriand wrote:
> No need to fiddle with pens, all I have to do is go out in the garage,
> measure the driveshaft length, jack up my TJ by the frame, and measure the
> drive shaft length again to confirm that it compresses, not extends. I've
> done this before, it's not theoretical, it's observable reality.
>
> /Peter
--
__________________________________________________ _________
tw
71 Bill Stroppe Baja Bronco
03 TJ Rubicon - Rubicon Express 4.5"
01 XJ Sport
There is a very fine line between "hobby" and "mental illness."
-- Dave Barry
Pronunciation: 'jEp
Function: noun
Date: 1940
Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
A small general-purpose motor vehicle with 80-inch wheelbase,
1/4-ton capacity, and four-wheel drive used by the U.S. army in
World War II.
(Please remove the OBVIOUS to reply by email)
__________________________________________________ _________
#160
Guest
Posts: n/a
Re: Black Diamond Suspension Lift Installed-questions
Oh, go ahead and throw reality into this!!!!!!
Peter Pontbriand wrote:
> No need to fiddle with pens, all I have to do is go out in the garage,
> measure the driveshaft length, jack up my TJ by the frame, and measure the
> drive shaft length again to confirm that it compresses, not extends. I've
> done this before, it's not theoretical, it's observable reality.
>
> /Peter
--
__________________________________________________ _________
tw
71 Bill Stroppe Baja Bronco
03 TJ Rubicon - Rubicon Express 4.5"
01 XJ Sport
There is a very fine line between "hobby" and "mental illness."
-- Dave Barry
Pronunciation: 'jEp
Function: noun
Date: 1940
Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
A small general-purpose motor vehicle with 80-inch wheelbase,
1/4-ton capacity, and four-wheel drive used by the U.S. army in
World War II.
(Please remove the OBVIOUS to reply by email)
__________________________________________________ _________
Peter Pontbriand wrote:
> No need to fiddle with pens, all I have to do is go out in the garage,
> measure the driveshaft length, jack up my TJ by the frame, and measure the
> drive shaft length again to confirm that it compresses, not extends. I've
> done this before, it's not theoretical, it's observable reality.
>
> /Peter
--
__________________________________________________ _________
tw
71 Bill Stroppe Baja Bronco
03 TJ Rubicon - Rubicon Express 4.5"
01 XJ Sport
There is a very fine line between "hobby" and "mental illness."
-- Dave Barry
Pronunciation: 'jEp
Function: noun
Date: 1940
Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
A small general-purpose motor vehicle with 80-inch wheelbase,
1/4-ton capacity, and four-wheel drive used by the U.S. army in
World War II.
(Please remove the OBVIOUS to reply by email)
__________________________________________________ _________