Re: Working on Brakes (especially Rear Drums) - TJ
 

Jack in the air thing?


"Mike Romain" <romainm@sympatico.ca> wrote in message
news:40E1DDD0.55148A82@sympatico.ca...
> Both.
>
> I can get my open rear spinning up both tires and sometimes the front as
> well, but the drum brakes seem to be better at slowly modifying the
> torque rather then the hit disks give.
>
> The valve is dynamic, it sends so much pressure to the rears, then
> shunts the rest front, then brings it back to the rear for the final
> stop.
>
> If the fronts stop really easy, no more pressure goes to the rears, if
> the fronts stop hard, you 'can' lock the rears as you come to a stop.
>
> I think that's why the jack in the air thing works so well to totally
> confuse folks.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's
>
> SB wrote:
> >
> > Hmm....so, with the limited slip....the whole brake trick to get rid of
the
> > single wheel spin....will that work in 2WD? or only 4??
> > "mabar" <mabar@NoSpamgrbonline.com> wrote in message
> > news:TK2dncYE8b_WxXzd4p2dnA@gbronline.com...
> > > Yep. On most cars, the front brakes do about 70% (+) of the braking.
On
> > the
> > > TJ, because of the extra short wheelbase, the fronts
> > > do MUCH more of the braking. The rears do very little of the actual
> > braking.
> > >
> > > Try this test. Raise the rear wheels off the ground with a floor jack
or
> > > jack stands. With the engine at IDLE and with the transfer case in
2-wheel
> > > drive, put the transmission in drive or 1st gear, then try to stop the
> > rear
> > > wheels from moving with only the foot brake. On my 6-cyl TJ with 3.73
rear
> > > axel ratio, it is almost impossible to stop the rears, even while
mashing
> > > the foot brake with all my might. Applying the parking brake will stop
the
> > > rears easily.
> > >
> > > Tom
> > >
> > > "SB" <chicbearsmook@hotmail.com> wrote in message
> > > news:O94Ec.322$T6i.195@news04.bloor.is.net.cable.r ogers.com...
> > > > Wow...do the front actually do that much?
> > > >
> > > > Sure feels like it the way the front dives down....
> > > > actually shared an arse clenching experience with a dog today!
Nosed
> > down
> > > > and skidded....but all's ok!
> > > >
> > > >
> > > > "mabar" <mabar@NoSpamgrbonline.com> wrote in message
> > > > news:W-OdnQ9Kgs_ZK33dRVn-sA@gbronline.com...
> > > > > Exactly. A combination valve is also called a proportioning valve.
It
> > > > > distributes the braking power heavily to the front brakes and
> > > > > much less so to the rears. On a TJ, the front brakes do the lion's
> > share
> > > > of
> > > > > the braking, probably 80 to 90%.
> > > > >
> > > > > Tom
> > >
> > >

Re: Working on Brakes (especially Rear Drums) - TJ
 

Jack in the air thing?


"Mike Romain" <romainm@sympatico.ca> wrote in message
news:40E1DDD0.55148A82@sympatico.ca...
> Both.
>
> I can get my open rear spinning up both tires and sometimes the front as
> well, but the drum brakes seem to be better at slowly modifying the
> torque rather then the hit disks give.
>
> The valve is dynamic, it sends so much pressure to the rears, then
> shunts the rest front, then brings it back to the rear for the final
> stop.
>
> If the fronts stop really easy, no more pressure goes to the rears, if
> the fronts stop hard, you 'can' lock the rears as you come to a stop.
>
> I think that's why the jack in the air thing works so well to totally
> confuse folks.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's
>
> SB wrote:
> >
> > Hmm....so, with the limited slip....the whole brake trick to get rid of
the
> > single wheel spin....will that work in 2WD? or only 4??
> > "mabar" <mabar@NoSpamgrbonline.com> wrote in message
> > news:TK2dncYE8b_WxXzd4p2dnA@gbronline.com...
> > > Yep. On most cars, the front brakes do about 70% (+) of the braking.
On
> > the
> > > TJ, because of the extra short wheelbase, the fronts
> > > do MUCH more of the braking. The rears do very little of the actual
> > braking.
> > >
> > > Try this test. Raise the rear wheels off the ground with a floor jack
or
> > > jack stands. With the engine at IDLE and with the transfer case in
2-wheel
> > > drive, put the transmission in drive or 1st gear, then try to stop the
> > rear
> > > wheels from moving with only the foot brake. On my 6-cyl TJ with 3.73
rear
> > > axel ratio, it is almost impossible to stop the rears, even while
mashing
> > > the foot brake with all my might. Applying the parking brake will stop
the
> > > rears easily.
> > >
> > > Tom
> > >
> > > "SB" <chicbearsmook@hotmail.com> wrote in message
> > > news:O94Ec.322$T6i.195@news04.bloor.is.net.cable.r ogers.com...
> > > > Wow...do the front actually do that much?
> > > >
> > > > Sure feels like it the way the front dives down....
> > > > actually shared an arse clenching experience with a dog today!
Nosed
> > down
> > > > and skidded....but all's ok!
> > > >
> > > >
> > > > "mabar" <mabar@NoSpamgrbonline.com> wrote in message
> > > > news:W-OdnQ9Kgs_ZK33dRVn-sA@gbronline.com...
> > > > > Exactly. A combination valve is also called a proportioning valve.
It
> > > > > distributes the braking power heavily to the front brakes and
> > > > > much less so to the rears. On a TJ, the front brakes do the lion's
> > share
> > > > of
> > > > > the braking, probably 80 to 90%.
> > > > >
> > > > > Tom
> > >
> > >

Re: Working on Brakes (especially Rear Drums) - TJ
 

Jack in the air thing?


"Mike Romain" <romainm@sympatico.ca> wrote in message
news:40E1DDD0.55148A82@sympatico.ca...
> Both.
>
> I can get my open rear spinning up both tires and sometimes the front as
> well, but the drum brakes seem to be better at slowly modifying the
> torque rather then the hit disks give.
>
> The valve is dynamic, it sends so much pressure to the rears, then
> shunts the rest front, then brings it back to the rear for the final
> stop.
>
> If the fronts stop really easy, no more pressure goes to the rears, if
> the fronts stop hard, you 'can' lock the rears as you come to a stop.
>
> I think that's why the jack in the air thing works so well to totally
> confuse folks.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's
>
> SB wrote:
> >
> > Hmm....so, with the limited slip....the whole brake trick to get rid of
the
> > single wheel spin....will that work in 2WD? or only 4??
> > "mabar" <mabar@NoSpamgrbonline.com> wrote in message
> > news:TK2dncYE8b_WxXzd4p2dnA@gbronline.com...
> > > Yep. On most cars, the front brakes do about 70% (+) of the braking.
On
> > the
> > > TJ, because of the extra short wheelbase, the fronts
> > > do MUCH more of the braking. The rears do very little of the actual
> > braking.
> > >
> > > Try this test. Raise the rear wheels off the ground with a floor jack
or
> > > jack stands. With the engine at IDLE and with the transfer case in
2-wheel
> > > drive, put the transmission in drive or 1st gear, then try to stop the
> > rear
> > > wheels from moving with only the foot brake. On my 6-cyl TJ with 3.73
rear
> > > axel ratio, it is almost impossible to stop the rears, even while
mashing
> > > the foot brake with all my might. Applying the parking brake will stop
the
> > > rears easily.
> > >
> > > Tom
> > >
> > > "SB" <chicbearsmook@hotmail.com> wrote in message
> > > news:O94Ec.322$T6i.195@news04.bloor.is.net.cable.r ogers.com...
> > > > Wow...do the front actually do that much?
> > > >
> > > > Sure feels like it the way the front dives down....
> > > > actually shared an arse clenching experience with a dog today!
Nosed
> > down
> > > > and skidded....but all's ok!
> > > >
> > > >
> > > > "mabar" <mabar@NoSpamgrbonline.com> wrote in message
> > > > news:W-OdnQ9Kgs_ZK33dRVn-sA@gbronline.com...
> > > > > Exactly. A combination valve is also called a proportioning valve.
It
> > > > > distributes the braking power heavily to the front brakes and
> > > > > much less so to the rears. On a TJ, the front brakes do the lion's
> > share
> > > > of
> > > > > the braking, probably 80 to 90%.
> > > > >
> > > > > Tom
> > >
> > >

Re: Working on Brakes (especially Rear Drums) - TJ
 

It sounds like you just need to adjust the brakes.





"Bob" <magicclaw@mac.com> wrote in message
news:47b769ae.0406290542.39c0c1a4@posting.google.c om...
> I'm pretty sure it's not just that.
>
> I've been getting a seat-of-the-pants feeling that my braking power
> has diminished of late; on the highway when traffic has stopped
> suddenly, I've found myself having to smash down on the brakes harder
> than before to get the jeep to stop in the same amount of time. While
> I can still lock the front up, it just doesn't seem to be as
> effective.
>
> This last weekend on the trail was my final straw: I was on a slight
> incline, and tried to go up a couple of rocks (I was in 2wd), and spun
> tires. So, I put the clutch in and hit the brake simultaneously, in
> order to put it in 4-low to get through the little bit of rocks. As
> soon as the clutch was in, the vehicle proceeded to roll back about
> 10+ feet, with me standing on the brake pedal (in retrospect, perhaps
> I should have pumped it). Either way, it was a bit freaky. The others
> in my group said my front wheels were locked up, but my rears were
> rolling, as I just rolled backward. It was like my rear brakes were
> doing nothing, and just the locking-up and subsequent dragging of my
> front wheels was all that stopped me.
>
> The braking improved a bit as the day progressed, but I decided maybe
> I'd better check and see if the brakes were (a) in good shape still
> and (b) not out of adjustment.
>
>
> Mike Romain <romainm@sympatico.ca> wrote in message
news:<40E08500.A9E6738F@sympatico.ca>...
> > Are you sure you aren't just seeing the effects of a properly working
> > combination valve?
> >
> > It acts like an anti lock brake for the rear wheels so they don't lock
> > up easy if at all. Normally you don't want the rears locking, you can
> > do 360's faster than you can blink if the rears lock up at speed.
> >
> > The combination valve stops them from locking until you are almost
> > stopped even if you really mash the pedal down.
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
> > Bob wrote:
> > >
> > > Hey...I am about to pull my brakes apart due to some persistent brake
> > > fade issues (dry or wet) I've been having with my rear brakes; I want
> > > to make sure everything is ok/fix whatever's wrong with them.
> > >
> > > Anyway, I'm going to start scouring the 'Net tonight to look for info
> > > how to work on brakes, diagrams, instructions, etc., especially for
> > > the rear drums (the front discs are more straight-forward from what I
> > > understand, and I'm pretty sure I'll be able to figure out what's
> > > going on with them a little easier).
> > >
> > > So, if anyone out there can provide me with any links to instructions
> > > they've found particularly useful in the past, that would be awesome.
> > > Pictures and diagrams are great, too. Bill, if you feel inclined to
> > > put up a link to the appropriate section from the FSM or something,
> > > that'd be awesome too. Also, any tips or suggestions what all I should
> > > do when servicing and checking my brakes (beyond the obvious
> > > inspection and replacement if necessary of the pads...) would be
> > > great!
> > >
> > > Thanks everyone.
> > >
> > > /Bob
> > >
> > > Applicable specs:
> > > 1997 TJ
> > > Dana 44 Rear (drum brakes)
> > > Dana 30 Front (disc brakes)
> > > Stock brakes front and rear.
> > > Last brake service performed 15 months ago.

Re: Working on Brakes (especially Rear Drums) - TJ
 

It sounds like you just need to adjust the brakes.





"Bob" <magicclaw@mac.com> wrote in message
news:47b769ae.0406290542.39c0c1a4@posting.google.c om...
> I'm pretty sure it's not just that.
>
> I've been getting a seat-of-the-pants feeling that my braking power
> has diminished of late; on the highway when traffic has stopped
> suddenly, I've found myself having to smash down on the brakes harder
> than before to get the jeep to stop in the same amount of time. While
> I can still lock the front up, it just doesn't seem to be as
> effective.
>
> This last weekend on the trail was my final straw: I was on a slight
> incline, and tried to go up a couple of rocks (I was in 2wd), and spun
> tires. So, I put the clutch in and hit the brake simultaneously, in
> order to put it in 4-low to get through the little bit of rocks. As
> soon as the clutch was in, the vehicle proceeded to roll back about
> 10+ feet, with me standing on the brake pedal (in retrospect, perhaps
> I should have pumped it). Either way, it was a bit freaky. The others
> in my group said my front wheels were locked up, but my rears were
> rolling, as I just rolled backward. It was like my rear brakes were
> doing nothing, and just the locking-up and subsequent dragging of my
> front wheels was all that stopped me.
>
> The braking improved a bit as the day progressed, but I decided maybe
> I'd better check and see if the brakes were (a) in good shape still
> and (b) not out of adjustment.
>
>
> Mike Romain <romainm@sympatico.ca> wrote in message
news:<40E08500.A9E6738F@sympatico.ca>...
> > Are you sure you aren't just seeing the effects of a properly working
> > combination valve?
> >
> > It acts like an anti lock brake for the rear wheels so they don't lock
> > up easy if at all. Normally you don't want the rears locking, you can
> > do 360's faster than you can blink if the rears lock up at speed.
> >
> > The combination valve stops them from locking until you are almost
> > stopped even if you really mash the pedal down.
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
> > Bob wrote:
> > >
> > > Hey...I am about to pull my brakes apart due to some persistent brake
> > > fade issues (dry or wet) I've been having with my rear brakes; I want
> > > to make sure everything is ok/fix whatever's wrong with them.
> > >
> > > Anyway, I'm going to start scouring the 'Net tonight to look for info
> > > how to work on brakes, diagrams, instructions, etc., especially for
> > > the rear drums (the front discs are more straight-forward from what I
> > > understand, and I'm pretty sure I'll be able to figure out what's
> > > going on with them a little easier).
> > >
> > > So, if anyone out there can provide me with any links to instructions
> > > they've found particularly useful in the past, that would be awesome.
> > > Pictures and diagrams are great, too. Bill, if you feel inclined to
> > > put up a link to the appropriate section from the FSM or something,
> > > that'd be awesome too. Also, any tips or suggestions what all I should
> > > do when servicing and checking my brakes (beyond the obvious
> > > inspection and replacement if necessary of the pads...) would be
> > > great!
> > >
> > > Thanks everyone.
> > >
> > > /Bob
> > >
> > > Applicable specs:
> > > 1997 TJ
> > > Dana 44 Rear (drum brakes)
> > > Dana 30 Front (disc brakes)
> > > Stock brakes front and rear.
> > > Last brake service performed 15 months ago.

Re: Working on Brakes (especially Rear Drums) - TJ
 

It sounds like you just need to adjust the brakes.





"Bob" <magicclaw@mac.com> wrote in message
news:47b769ae.0406290542.39c0c1a4@posting.google.c om...
> I'm pretty sure it's not just that.
>
> I've been getting a seat-of-the-pants feeling that my braking power
> has diminished of late; on the highway when traffic has stopped
> suddenly, I've found myself having to smash down on the brakes harder
> than before to get the jeep to stop in the same amount of time. While
> I can still lock the front up, it just doesn't seem to be as
> effective.
>
> This last weekend on the trail was my final straw: I was on a slight
> incline, and tried to go up a couple of rocks (I was in 2wd), and spun
> tires. So, I put the clutch in and hit the brake simultaneously, in
> order to put it in 4-low to get through the little bit of rocks. As
> soon as the clutch was in, the vehicle proceeded to roll back about
> 10+ feet, with me standing on the brake pedal (in retrospect, perhaps
> I should have pumped it). Either way, it was a bit freaky. The others
> in my group said my front wheels were locked up, but my rears were
> rolling, as I just rolled backward. It was like my rear brakes were
> doing nothing, and just the locking-up and subsequent dragging of my
> front wheels was all that stopped me.
>
> The braking improved a bit as the day progressed, but I decided maybe
> I'd better check and see if the brakes were (a) in good shape still
> and (b) not out of adjustment.
>
>
> Mike Romain <romainm@sympatico.ca> wrote in message
news:<40E08500.A9E6738F@sympatico.ca>...
> > Are you sure you aren't just seeing the effects of a properly working
> > combination valve?
> >
> > It acts like an anti lock brake for the rear wheels so they don't lock
> > up easy if at all. Normally you don't want the rears locking, you can
> > do 360's faster than you can blink if the rears lock up at speed.
> >
> > The combination valve stops them from locking until you are almost
> > stopped even if you really mash the pedal down.
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
> > Bob wrote:
> > >
> > > Hey...I am about to pull my brakes apart due to some persistent brake
> > > fade issues (dry or wet) I've been having with my rear brakes; I want
> > > to make sure everything is ok/fix whatever's wrong with them.
> > >
> > > Anyway, I'm going to start scouring the 'Net tonight to look for info
> > > how to work on brakes, diagrams, instructions, etc., especially for
> > > the rear drums (the front discs are more straight-forward from what I
> > > understand, and I'm pretty sure I'll be able to figure out what's
> > > going on with them a little easier).
> > >
> > > So, if anyone out there can provide me with any links to instructions
> > > they've found particularly useful in the past, that would be awesome.
> > > Pictures and diagrams are great, too. Bill, if you feel inclined to
> > > put up a link to the appropriate section from the FSM or something,
> > > that'd be awesome too. Also, any tips or suggestions what all I should
> > > do when servicing and checking my brakes (beyond the obvious
> > > inspection and replacement if necessary of the pads...) would be
> > > great!
> > >
> > > Thanks everyone.
> > >
> > > /Bob
> > >
> > > Applicable specs:
> > > 1997 TJ
> > > Dana 44 Rear (drum brakes)
> > > Dana 30 Front (disc brakes)
> > > Stock brakes front and rear.
> > > Last brake service performed 15 months ago.

Re: Working on Brakes (especially Rear Drums) - TJ
 

It sounds like you just need to adjust the brakes.





"Bob" <magicclaw@mac.com> wrote in message
news:47b769ae.0406290542.39c0c1a4@posting.google.c om...
> I'm pretty sure it's not just that.
>
> I've been getting a seat-of-the-pants feeling that my braking power
> has diminished of late; on the highway when traffic has stopped
> suddenly, I've found myself having to smash down on the brakes harder
> than before to get the jeep to stop in the same amount of time. While
> I can still lock the front up, it just doesn't seem to be as
> effective.
>
> This last weekend on the trail was my final straw: I was on a slight
> incline, and tried to go up a couple of rocks (I was in 2wd), and spun
> tires. So, I put the clutch in and hit the brake simultaneously, in
> order to put it in 4-low to get through the little bit of rocks. As
> soon as the clutch was in, the vehicle proceeded to roll back about
> 10+ feet, with me standing on the brake pedal (in retrospect, perhaps
> I should have pumped it). Either way, it was a bit freaky. The others
> in my group said my front wheels were locked up, but my rears were
> rolling, as I just rolled backward. It was like my rear brakes were
> doing nothing, and just the locking-up and subsequent dragging of my
> front wheels was all that stopped me.
>
> The braking improved a bit as the day progressed, but I decided maybe
> I'd better check and see if the brakes were (a) in good shape still
> and (b) not out of adjustment.
>
>
> Mike Romain <romainm@sympatico.ca> wrote in message
news:<40E08500.A9E6738F@sympatico.ca>...
> > Are you sure you aren't just seeing the effects of a properly working
> > combination valve?
> >
> > It acts like an anti lock brake for the rear wheels so they don't lock
> > up easy if at all. Normally you don't want the rears locking, you can
> > do 360's faster than you can blink if the rears lock up at speed.
> >
> > The combination valve stops them from locking until you are almost
> > stopped even if you really mash the pedal down.
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
> > Bob wrote:
> > >
> > > Hey...I am about to pull my brakes apart due to some persistent brake
> > > fade issues (dry or wet) I've been having with my rear brakes; I want
> > > to make sure everything is ok/fix whatever's wrong with them.
> > >
> > > Anyway, I'm going to start scouring the 'Net tonight to look for info
> > > how to work on brakes, diagrams, instructions, etc., especially for
> > > the rear drums (the front discs are more straight-forward from what I
> > > understand, and I'm pretty sure I'll be able to figure out what's
> > > going on with them a little easier).
> > >
> > > So, if anyone out there can provide me with any links to instructions
> > > they've found particularly useful in the past, that would be awesome.
> > > Pictures and diagrams are great, too. Bill, if you feel inclined to
> > > put up a link to the appropriate section from the FSM or something,
> > > that'd be awesome too. Also, any tips or suggestions what all I should
> > > do when servicing and checking my brakes (beyond the obvious
> > > inspection and replacement if necessary of the pads...) would be
> > > great!
> > >
> > > Thanks everyone.
> > >
> > > /Bob
> > >
> > > Applicable specs:
> > > 1997 TJ
> > > Dana 44 Rear (drum brakes)
> > > Dana 30 Front (disc brakes)
> > > Stock brakes front and rear.
> > > Last brake service performed 15 months ago.

Re: Working on Brakes (especially Rear Drums) - TJ
 

Yes, what the previous poster said about jacking up the rear end and
putting it in gear then trying to stop the tires in the air with the
brakes. It don't work for ----.

Mike

SB wrote:
>
> Jack in the air thing?
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:40E1DDD0.55148A82@sympatico.ca...
> > Both.
> >
> > I can get my open rear spinning up both tires and sometimes the front as
> > well, but the drum brakes seem to be better at slowly modifying the
> > torque rather then the hit disks give.
> >
> > The valve is dynamic, it sends so much pressure to the rears, then
> > shunts the rest front, then brings it back to the rear for the final
> > stop.
> >
> > If the fronts stop really easy, no more pressure goes to the rears, if
> > the fronts stop hard, you 'can' lock the rears as you come to a stop.
> >
> > I think that's why the jack in the air thing works so well to totally
> > confuse folks.
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
> > SB wrote:
> > >
> > > Hmm....so, with the limited slip....the whole brake trick to get rid of
> the
> > > single wheel spin....will that work in 2WD? or only 4??
> > > "mabar" <mabar@NoSpamgrbonline.com> wrote in message
> > > news:TK2dncYE8b_WxXzd4p2dnA@gbronline.com...
> > > > Yep. On most cars, the front brakes do about 70% (+) of the braking.
> On
> > > the
> > > > TJ, because of the extra short wheelbase, the fronts
> > > > do MUCH more of the braking. The rears do very little of the actual
> > > braking.
> > > >
> > > > Try this test. Raise the rear wheels off the ground with a floor jack
> or
> > > > jack stands. With the engine at IDLE and with the transfer case in
> 2-wheel
> > > > drive, put the transmission in drive or 1st gear, then try to stop the
> > > rear
> > > > wheels from moving with only the foot brake. On my 6-cyl TJ with 3.73
> rear
> > > > axel ratio, it is almost impossible to stop the rears, even while
> mashing
> > > > the foot brake with all my might. Applying the parking brake will stop
> the
> > > > rears easily.
> > > >
> > > > Tom
> > > >
> > > > "SB" <chicbearsmook@hotmail.com> wrote in message
> > > > news:O94Ec.322$T6i.195@news04.bloor.is.net.cable.r ogers.com...
> > > > > Wow...do the front actually do that much?
> > > > >
> > > > > Sure feels like it the way the front dives down....
> > > > > actually shared an arse clenching experience with a dog today!
> Nosed
> > > down
> > > > > and skidded....but all's ok!
> > > > >
> > > > >
> > > > > "mabar" <mabar@NoSpamgrbonline.com> wrote in message
> > > > > news:W-OdnQ9Kgs_ZK33dRVn-sA@gbronline.com...
> > > > > > Exactly. A combination valve is also called a proportioning valve.
> It
> > > > > > distributes the braking power heavily to the front brakes and
> > > > > > much less so to the rears. On a TJ, the front brakes do the lion's
> > > share
> > > > > of
> > > > > > the braking, probably 80 to 90%.
> > > > > >
> > > > > > Tom
> > > >
> > > >

Re: Working on Brakes (especially Rear Drums) - TJ
 

Yes, what the previous poster said about jacking up the rear end and
putting it in gear then trying to stop the tires in the air with the
brakes. It don't work for ----.

Mike

SB wrote:
>
> Jack in the air thing?
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:40E1DDD0.55148A82@sympatico.ca...
> > Both.
> >
> > I can get my open rear spinning up both tires and sometimes the front as
> > well, but the drum brakes seem to be better at slowly modifying the
> > torque rather then the hit disks give.
> >
> > The valve is dynamic, it sends so much pressure to the rears, then
> > shunts the rest front, then brings it back to the rear for the final
> > stop.
> >
> > If the fronts stop really easy, no more pressure goes to the rears, if
> > the fronts stop hard, you 'can' lock the rears as you come to a stop.
> >
> > I think that's why the jack in the air thing works so well to totally
> > confuse folks.
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
> > SB wrote:
> > >
> > > Hmm....so, with the limited slip....the whole brake trick to get rid of
> the
> > > single wheel spin....will that work in 2WD? or only 4??
> > > "mabar" <mabar@NoSpamgrbonline.com> wrote in message
> > > news:TK2dncYE8b_WxXzd4p2dnA@gbronline.com...
> > > > Yep. On most cars, the front brakes do about 70% (+) of the braking.
> On
> > > the
> > > > TJ, because of the extra short wheelbase, the fronts
> > > > do MUCH more of the braking. The rears do very little of the actual
> > > braking.
> > > >
> > > > Try this test. Raise the rear wheels off the ground with a floor jack
> or
> > > > jack stands. With the engine at IDLE and with the transfer case in
> 2-wheel
> > > > drive, put the transmission in drive or 1st gear, then try to stop the
> > > rear
> > > > wheels from moving with only the foot brake. On my 6-cyl TJ with 3.73
> rear
> > > > axel ratio, it is almost impossible to stop the rears, even while
> mashing
> > > > the foot brake with all my might. Applying the parking brake will stop
> the
> > > > rears easily.
> > > >
> > > > Tom
> > > >
> > > > "SB" <chicbearsmook@hotmail.com> wrote in message
> > > > news:O94Ec.322$T6i.195@news04.bloor.is.net.cable.r ogers.com...
> > > > > Wow...do the front actually do that much?
> > > > >
> > > > > Sure feels like it the way the front dives down....
> > > > > actually shared an arse clenching experience with a dog today!
> Nosed
> > > down
> > > > > and skidded....but all's ok!
> > > > >
> > > > >
> > > > > "mabar" <mabar@NoSpamgrbonline.com> wrote in message
> > > > > news:W-OdnQ9Kgs_ZK33dRVn-sA@gbronline.com...
> > > > > > Exactly. A combination valve is also called a proportioning valve.
> It
> > > > > > distributes the braking power heavily to the front brakes and
> > > > > > much less so to the rears. On a TJ, the front brakes do the lion's
> > > share
> > > > > of
> > > > > > the braking, probably 80 to 90%.
> > > > > >
> > > > > > Tom
> > > >
> > > >

Re: Working on Brakes (especially Rear Drums) - TJ
 

Yes, what the previous poster said about jacking up the rear end and
putting it in gear then trying to stop the tires in the air with the
brakes. It don't work for ----.

Mike

SB wrote:
>
> Jack in the air thing?
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:40E1DDD0.55148A82@sympatico.ca...
> > Both.
> >
> > I can get my open rear spinning up both tires and sometimes the front as
> > well, but the drum brakes seem to be better at slowly modifying the
> > torque rather then the hit disks give.
> >
> > The valve is dynamic, it sends so much pressure to the rears, then
> > shunts the rest front, then brings it back to the rear for the final
> > stop.
> >
> > If the fronts stop really easy, no more pressure goes to the rears, if
> > the fronts stop hard, you 'can' lock the rears as you come to a stop.
> >
> > I think that's why the jack in the air thing works so well to totally
> > confuse folks.
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
> > SB wrote:
> > >
> > > Hmm....so, with the limited slip....the whole brake trick to get rid of
> the
> > > single wheel spin....will that work in 2WD? or only 4??
> > > "mabar" <mabar@NoSpamgrbonline.com> wrote in message
> > > news:TK2dncYE8b_WxXzd4p2dnA@gbronline.com...
> > > > Yep. On most cars, the front brakes do about 70% (+) of the braking.
> On
> > > the
> > > > TJ, because of the extra short wheelbase, the fronts
> > > > do MUCH more of the braking. The rears do very little of the actual
> > > braking.
> > > >
> > > > Try this test. Raise the rear wheels off the ground with a floor jack
> or
> > > > jack stands. With the engine at IDLE and with the transfer case in
> 2-wheel
> > > > drive, put the transmission in drive or 1st gear, then try to stop the
> > > rear
> > > > wheels from moving with only the foot brake. On my 6-cyl TJ with 3.73
> rear
> > > > axel ratio, it is almost impossible to stop the rears, even while
> mashing
> > > > the foot brake with all my might. Applying the parking brake will stop
> the
> > > > rears easily.
> > > >
> > > > Tom
> > > >
> > > > "SB" <chicbearsmook@hotmail.com> wrote in message
> > > > news:O94Ec.322$T6i.195@news04.bloor.is.net.cable.r ogers.com...
> > > > > Wow...do the front actually do that much?
> > > > >
> > > > > Sure feels like it the way the front dives down....
> > > > > actually shared an arse clenching experience with a dog today!
> Nosed
> > > down
> > > > > and skidded....but all's ok!
> > > > >
> > > > >
> > > > > "mabar" <mabar@NoSpamgrbonline.com> wrote in message
> > > > > news:W-OdnQ9Kgs_ZK33dRVn-sA@gbronline.com...
> > > > > > Exactly. A combination valve is also called a proportioning valve.
> It
> > > > > > distributes the braking power heavily to the front brakes and
> > > > > > much less so to the rears. On a TJ, the front brakes do the lion's
> > > share
> > > > > of
> > > > > > the braking, probably 80 to 90%.
> > > > > >
> > > > > > Tom
> > > >
> > > >