Steve G

Absolutely. Sound travels up the driveshafts and throughout the drivetrain.
Re the suggestion of posi lube, chatter of posi clutches is only heard going
around a corner. Posi clutches aren't moving when going straight ahead
unless on a slippery surface where one wheel is attempting to spin and the
other not. The key to making these kinds of diagnosis is paying very close
attention to the specific circumstances surrounding the noise, coast/ load/
tied entirely to speed, only at a corner, warm, cold, etc.
Steve
"Eric" <gymrat@***.net> wrote in message
news:uATOb.23829$ii6.6953@okepread05...
> But would the diff make loud enough noises to be heard/felt in the cabin?
>
> Eric
> "Steve" <xjlfter@bogus.com> wrote in message
> news:1jSOb.67875$IF6.1612418@ursa-nb00s0.nbnet.nb.ca...
> > If there is water in your differential you might hear the gears chewing
> > up the ice from a cold start. If you suspect this, put a pan or bucket
> > under your diff and remove the cover to let the oil out. While you're in
> > there, check the gears for any chips or missing teeth. If you can, lift
> > one or both of the rear tires so you can rotate the gears to inspect.
> > Use a quality synthetic gear oil with a good cold-temp viscosity when
> > you refill.
> >
> > Steve
> > 90 XJ
> >
> > Eric wrote:
> > > Ok, my 00 XJ (4.0L, Auto, 8.25 rear) is giving me some strange noises,
> and
> > > they are really too intermittent to pin down. Thought you guys might
> have
> > > some ideas. It only started recently and seems to happen the most
> frequent
> > > when it is really cold out and it hasn't had much time to warm up. It
> > > doesn't happen every time under these circumstances, but that seems to
> be
> > > when it happens the most.
> > >
> > > Basically, it is a loud.. noise.. upon acceleration, and only when
> starting
> > > from a standstill and only when giving it a little more gas than
usual.
> > > Almost like a rattle, but deeper, coming from the rear. I thought it
> might
> > > be the exhaust pipe rattle against my shackle (I have 2" extended
> shackles
> > > and one touches the exhaust pipe -- yes, yes I need to cut it..).
That
> > > doesn't make sense, though, because it would happen all the time...
> > >
> > > Anyhow, could this be the rear u-joint? How would I check it? Could
it
> be
> > > something in the diff (doubtful)? I don't know, but the noise is
pretty
> > > loud. Loud enough to really get our attention today.
> > >
> > > Thanks guys.
> > >
> > > Eric
> > >
> > >
> >
>
>

Steve G

Absolutely. Sound travels up the driveshafts and throughout the drivetrain.
Re the suggestion of posi lube, chatter of posi clutches is only heard going
around a corner. Posi clutches aren't moving when going straight ahead
unless on a slippery surface where one wheel is attempting to spin and the
other not. The key to making these kinds of diagnosis is paying very close
attention to the specific circumstances surrounding the noise, coast/ load/
tied entirely to speed, only at a corner, warm, cold, etc.
Steve
"Eric" <gymrat@***.net> wrote in message
news:uATOb.23829$ii6.6953@okepread05...
> But would the diff make loud enough noises to be heard/felt in the cabin?
>
> Eric
> "Steve" <xjlfter@bogus.com> wrote in message
> news:1jSOb.67875$IF6.1612418@ursa-nb00s0.nbnet.nb.ca...
> > If there is water in your differential you might hear the gears chewing
> > up the ice from a cold start. If you suspect this, put a pan or bucket
> > under your diff and remove the cover to let the oil out. While you're in
> > there, check the gears for any chips or missing teeth. If you can, lift
> > one or both of the rear tires so you can rotate the gears to inspect.
> > Use a quality synthetic gear oil with a good cold-temp viscosity when
> > you refill.
> >
> > Steve
> > 90 XJ
> >
> > Eric wrote:
> > > Ok, my 00 XJ (4.0L, Auto, 8.25 rear) is giving me some strange noises,
> and
> > > they are really too intermittent to pin down. Thought you guys might
> have
> > > some ideas. It only started recently and seems to happen the most
> frequent
> > > when it is really cold out and it hasn't had much time to warm up. It
> > > doesn't happen every time under these circumstances, but that seems to
> be
> > > when it happens the most.
> > >
> > > Basically, it is a loud.. noise.. upon acceleration, and only when
> starting
> > > from a standstill and only when giving it a little more gas than
usual.
> > > Almost like a rattle, but deeper, coming from the rear. I thought it
> might
> > > be the exhaust pipe rattle against my shackle (I have 2" extended
> shackles
> > > and one touches the exhaust pipe -- yes, yes I need to cut it..).
That
> > > doesn't make sense, though, because it would happen all the time...
> > >
> > > Anyhow, could this be the rear u-joint? How would I check it? Could
it
> be
> > > something in the diff (doubtful)? I don't know, but the noise is
pretty
> > > loud. Loud enough to really get our attention today.
> > >
> > > Thanks guys.
> > >
> > > Eric
> > >
> > >
> >
>
>

Just Taylor

On Mon, 19 Jan 2004 19:28:50 GMT, Rich Hampel <RhmpL33@nospam.net>
wrote:

>The Transmission mount is notorius for 'sagging' and if the shaft angle
>changes much you will get 'noise' from the U joints. To check the
>mount, simply put a floor jack under the trans and slowly lift it, if
>the mount is broken the mount will totally lift off the crossbar - be
>careful not to lift too far or you WILL break a good mount. You can
>buy and install a new mount and most that Ive replaced require 1/4"
>spacers (stack of washers under the trans mount) to bring the prop
>shaft angtle back to spec.
>
>If the the differential is a positrac, dont forget that you need to add
>positrac additive to keep the clutch plates from 'grabbing'. I dont
>use positrac lube but use "Lucas Oil Stabilizer" - to take up the worn
>clearances of a worn diff .... the stuff has the apparent viscosity of
>a 140 wt. lube oil and doesnt need the positrac. lube additive.

Do you use the Lucas product alone or as an additive? If so, what do
you use along with the Lucas Oil Stabilizer?


--
Taylor

'89 Audi 200
'03 Audi S6 Avant
'98 Jeep Cherokee Sport

Just Taylor

On Mon, 19 Jan 2004 19:28:50 GMT, Rich Hampel <RhmpL33@nospam.net>
wrote:

>The Transmission mount is notorius for 'sagging' and if the shaft angle
>changes much you will get 'noise' from the U joints. To check the
>mount, simply put a floor jack under the trans and slowly lift it, if
>the mount is broken the mount will totally lift off the crossbar - be
>careful not to lift too far or you WILL break a good mount. You can
>buy and install a new mount and most that Ive replaced require 1/4"
>spacers (stack of washers under the trans mount) to bring the prop
>shaft angtle back to spec.
>
>If the the differential is a positrac, dont forget that you need to add
>positrac additive to keep the clutch plates from 'grabbing'. I dont
>use positrac lube but use "Lucas Oil Stabilizer" - to take up the worn
>clearances of a worn diff .... the stuff has the apparent viscosity of
>a 140 wt. lube oil and doesnt need the positrac. lube additive.

Do you use the Lucas product alone or as an additive? If so, what do
you use along with the Lucas Oil Stabilizer?


--
Taylor

'89 Audi 200
'03 Audi S6 Avant
'98 Jeep Cherokee Sport

Just Taylor

On Mon, 19 Jan 2004 19:28:50 GMT, Rich Hampel <RhmpL33@nospam.net>
wrote:

>The Transmission mount is notorius for 'sagging' and if the shaft angle
>changes much you will get 'noise' from the U joints. To check the
>mount, simply put a floor jack under the trans and slowly lift it, if
>the mount is broken the mount will totally lift off the crossbar - be
>careful not to lift too far or you WILL break a good mount. You can
>buy and install a new mount and most that Ive replaced require 1/4"
>spacers (stack of washers under the trans mount) to bring the prop
>shaft angtle back to spec.
>
>If the the differential is a positrac, dont forget that you need to add
>positrac additive to keep the clutch plates from 'grabbing'. I dont
>use positrac lube but use "Lucas Oil Stabilizer" - to take up the worn
>clearances of a worn diff .... the stuff has the apparent viscosity of
>a 140 wt. lube oil and doesnt need the positrac. lube additive.

Do you use the Lucas product alone or as an additive? If so, what do
you use along with the Lucas Oil Stabilizer?


--
Taylor

'89 Audi 200
'03 Audi S6 Avant
'98 Jeep Cherokee Sport

Rich Hampel

I use a full quart of the stabilizer and then add to full with regular
gear oil.
What started this was that I had 'wierd' wear patterns develop due to
movement in one of the 'crush seals' holding the pinion in place. The
noise settled down with the stabilizer. I changed the lube a year
later and added just plain gear oil and posi-trac lube - noise came
back immediately and I then replaced with the stabilizer and oil to
quiet it down.

In article <401574b1.14053758@wilhelp.com>, Just Taylor
<taylor@wilhelp.com> wrote:

> On Mon, 19 Jan 2004 19:28:50 GMT, Rich Hampel <RhmpL33@nospam.net>
> wrote:
>
> >The Transmission mount is notorius for 'sagging' and if the shaft angle
> >changes much you will get 'noise' from the U joints. To check the
> >mount, simply put a floor jack under the trans and slowly lift it, if
> >the mount is broken the mount will totally lift off the crossbar - be
> >careful not to lift too far or you WILL break a good mount. You can
> >buy and install a new mount and most that Ive replaced require 1/4"
> >spacers (stack of washers under the trans mount) to bring the prop
> >shaft angtle back to spec.
> >
> >If the the differential is a positrac, dont forget that you need to add
> >positrac additive to keep the clutch plates from 'grabbing'. I dont
> >use positrac lube but use "Lucas Oil Stabilizer" - to take up the worn
> >clearances of a worn diff .... the stuff has the apparent viscosity of
> >a 140 wt. lube oil and doesnt need the positrac. lube additive.
>
> Do you use the Lucas product alone or as an additive? If so, what do
> you use along with the Lucas Oil Stabilizer?
>
>
> --
> Taylor
>
> '89 Audi 200
> '03 Audi S6 Avant
> '98 Jeep Cherokee Sport

Rich Hampel

I use a full quart of the stabilizer and then add to full with regular
gear oil.
What started this was that I had 'wierd' wear patterns develop due to
movement in one of the 'crush seals' holding the pinion in place. The
noise settled down with the stabilizer. I changed the lube a year
later and added just plain gear oil and posi-trac lube - noise came
back immediately and I then replaced with the stabilizer and oil to
quiet it down.

In article <401574b1.14053758@wilhelp.com>, Just Taylor
<taylor@wilhelp.com> wrote:

> On Mon, 19 Jan 2004 19:28:50 GMT, Rich Hampel <RhmpL33@nospam.net>
> wrote:
>
> >The Transmission mount is notorius for 'sagging' and if the shaft angle
> >changes much you will get 'noise' from the U joints. To check the
> >mount, simply put a floor jack under the trans and slowly lift it, if
> >the mount is broken the mount will totally lift off the crossbar - be
> >careful not to lift too far or you WILL break a good mount. You can
> >buy and install a new mount and most that Ive replaced require 1/4"
> >spacers (stack of washers under the trans mount) to bring the prop
> >shaft angtle back to spec.
> >
> >If the the differential is a positrac, dont forget that you need to add
> >positrac additive to keep the clutch plates from 'grabbing'. I dont
> >use positrac lube but use "Lucas Oil Stabilizer" - to take up the worn
> >clearances of a worn diff .... the stuff has the apparent viscosity of
> >a 140 wt. lube oil and doesnt need the positrac. lube additive.
>
> Do you use the Lucas product alone or as an additive? If so, what do
> you use along with the Lucas Oil Stabilizer?
>
>
> --
> Taylor
>
> '89 Audi 200
> '03 Audi S6 Avant
> '98 Jeep Cherokee Sport

Rich Hampel

I use a full quart of the stabilizer and then add to full with regular
gear oil.
What started this was that I had 'wierd' wear patterns develop due to
movement in one of the 'crush seals' holding the pinion in place. The
noise settled down with the stabilizer. I changed the lube a year
later and added just plain gear oil and posi-trac lube - noise came
back immediately and I then replaced with the stabilizer and oil to
quiet it down.

In article <401574b1.14053758@wilhelp.com>, Just Taylor
<taylor@wilhelp.com> wrote:

> On Mon, 19 Jan 2004 19:28:50 GMT, Rich Hampel <RhmpL33@nospam.net>
> wrote:
>
> >The Transmission mount is notorius for 'sagging' and if the shaft angle
> >changes much you will get 'noise' from the U joints. To check the
> >mount, simply put a floor jack under the trans and slowly lift it, if
> >the mount is broken the mount will totally lift off the crossbar - be
> >careful not to lift too far or you WILL break a good mount. You can
> >buy and install a new mount and most that Ive replaced require 1/4"
> >spacers (stack of washers under the trans mount) to bring the prop
> >shaft angtle back to spec.
> >
> >If the the differential is a positrac, dont forget that you need to add
> >positrac additive to keep the clutch plates from 'grabbing'. I dont
> >use positrac lube but use "Lucas Oil Stabilizer" - to take up the worn
> >clearances of a worn diff .... the stuff has the apparent viscosity of
> >a 140 wt. lube oil and doesnt need the positrac. lube additive.
>
> Do you use the Lucas product alone or as an additive? If so, what do
> you use along with the Lucas Oil Stabilizer?
>
>
> --
> Taylor
>
> '89 Audi 200
> '03 Audi S6 Avant
> '98 Jeep Cherokee Sport