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mattbred
October 16th, 2007, 09:02
I have an '89 Cherokee 4.0 Litre with a Peugeot BA/10 manual transmission and I was wondering if any of these signs point to bad mounts somewhere.

When I'm driving in a torquey gear, say second, and I let go of the gas, the whole jeep rocks back and forth, and you can see the shifter move forward and backwards as well. The same thing happens if I step on the gas, no matter how softly I try it. Once the slack is picked up, it feels absolutely fine. This is pretty nauseating after a while and hard on passengers.

What's bothering me is it seems like there is excessive drive line slack. The U-joints seem fairly new and I can't find any play in them, however if I push on the rear drive shaft, it does move the transfer case and transmission pretty good.

Any ideas?

billyjp2
October 16th, 2007, 09:12
take a flashlight and look at the motor mounts, you can almost always see what kind of condition the rubber is in. it sounds like a tranny mount, but to be honest i've only had them go bad in my f-150, never in an xj so take it for what its worth.

mattbred
October 16th, 2007, 09:23
Well I did look at the upper passenger side motor mount and it looked OK from what I could tell.

87manche
October 16th, 2007, 09:26
the drivers side mount is the one that takes most of the abuse. It usually fails first.

easy way to check is to pop the hood and snap the throttle a few times. The motr should rock a bit, but it shouldn't be excessive.
If it moves more than a few inches the mounts are probably shot.

89xj
October 16th, 2007, 09:47
tranny mount for the peugot is expensive and weak in general. when i would hit a pothole or speedbump the shifter would move all over the place. i got mine at the dealer but there are some jeep sites that may have it.

i replaced mine a few years ago. the tranny still moved a bit more than i liked. to get some of the slop out, i pryed the tranny up a bit and inserted sway bar link bushings between the tranny and the mount. no extra movement and still flexs enough. i also run daystar poly engine mounts. they vibed at first but the vibes went away.

for the engine mounts, the driverside mount needs to be ground down slightly to fit and the oil adapter(replace the orings while its off) needs to be removed during installation to get the passengerside mount on.

Jess
October 16th, 2007, 12:20
tranny mount for the peugot is expensive and weak in general. when i would hit a pothole or speedbump the shifter would move all over the place. i got mine at the dealer but there are some jeep sites that may have it.

i replaced mine a few years ago. the tranny still moved a bit more than i liked. to get some of the slop out, i pryed the tranny up a bit and inserted sway bar link bushings between the tranny and the mount. no extra movement and still flexs enough. i also run daystar poly engine mounts. they vibed at first but the vibes went away.

for the engine mounts, the driverside mount needs to be ground down slightly to fit and the oil adapter(replace the orings while its off) needs to be removed during installation to get the passengerside mount on.

Don't start grinding your mounts until you try to fit them. Some do need to be ground but not all.....measure twice cut once.

It is however a good idea to do the oil filter o-rings while you are in there though.

89xj
October 16th, 2007, 12:50
Don't start grinding your mounts until you try to fit them. Some do need to be ground but not all.....measure twice cut once.

It is however a good idea to do the oil filter o-rings while you are in there though.

let me restate, with the daystar poly mounts from rustys, i had to grind.

who would grind them before dry fitting them??? how would they know where to grind and how much?

mattbred
October 16th, 2007, 16:30
Ok I'll check the motor mounts. I took it for a drive today and really payed attention and damn its really really jerky. Not a single jerk either, it rocks back and forth a good 3 times before settling down on the torque. this is both letting off the gas, and getting on the gas. Also, I listened well and every time it rocked I heard a popping sound from underneath the floor pan. Transmission I'm guessing.

selarep
October 16th, 2007, 19:58
Mine does it, and I have a 98 with the ax-15. I replaced my motor AND tranny mounts... still does it. Cant figure it out yet... though it was the motor mounts but replaced those then i did the tranny mounts and still... oh well. it runs good.

darjevon
October 16th, 2007, 20:19
The tranny mount on my 99 was shot when I replaced it last year. My drivers side motor mount had basically no rubber left, and the left mount was bent. :gee:

the mounts are likely your problem

Fehron
October 17th, 2007, 17:38
My 89 five speed jerks and shimmies sometimes on take off or in a bind like going over a small hump real slow. Every now and again if I'm shifting hard, I will hear a banging sound. Other than that it is smooth on the highway and everywhere else.
I will try the cracking the throttle at the throttle body and watch for excessive motor movement.

89xj
October 18th, 2007, 11:47
1989, 5sp(peugot) with poly engine mounts and after reinforcing the weak tranny mount, i now get no movement over bumps or hard throttles and no vibs. it does have enough movement so nothing breaks. i dealt with the loose tranny mounts for years untill i reinforced it.

mattbred
October 18th, 2007, 13:12
Can you describe exactly how you reinforced it? Also can you take pictures? I'd love to fix this annoyingness.

Harlee&Tahoe
October 18th, 2007, 13:27
I have the same problems. Just ordered a Crown (http://www.crownautomotive.net/catalog/engine/4.0L_2.html#53) replacement trans mount
I'm also going to look into M.O.R.E. (http://www.mountainoffroad.com/more.htm) rubber mounts for more permanent solution
I've been rubbing front driveshaft on header downtube(have a new piece redesigned from pacesetter to replace self clearenced piece)

mattbred
October 18th, 2007, 14:01
Where did you order the replacement mount? Teamcherokee.com?

Let me know how it goes!

IslanderOffRoad
October 18th, 2007, 14:09
one of the biggest signs is your fan going through the rad.

at least it was for me

IslanderOffRoad
October 18th, 2007, 14:10
Mine does it, and I have a 98 with the ax-15. I replaced my motor AND tranny mounts... still does it. Cant figure it out yet... though it was the motor mounts but replaced those then i did the tranny mounts and still... oh well. it runs good.

yeah, the 5spds behave weird sometimes at really low speeds, people look at me like i'm nuts in the parking lot.

89xj
October 19th, 2007, 11:34
Can you describe exactly how you reinforced it? Also can you take pictures? I'd love to fix this annoyingness.

on the peugot, the mount for the tranny is v-shaped. there is nothing holding the tranny up in the middle where it is flat. i used poly sway bar end link bushings to reinforce it. pry the tranny up and slide the bushings(1 on each side) between the flat spot of the tranny and mount.

JAS
October 19th, 2007, 11:58
For my motor mounts they looked like this.

On the left you have the M.O.R.E mount and on the right you have the stock mounts

http://webpages.charter.net/laurajeff44/Exhaust/P9150008_Piggig.jpg

As you can see the drivers side mount was torn nearly in half. The passengers side was super soft and mushy.

Harlee&Tahoe
October 19th, 2007, 18:29
Just ordered my Bombproof mounts last night. Fix it and forget it!

mattbred
November 10th, 2007, 17:46
Alright so I put in some rubber sway bar bushings in between the transmission and the mount and it helped tremendously! I reccomend this to EVERYONE owning a Cherokee with a Pegeuot.

I wonder if polyurethane would work better than rubber? They were an extra 10 dollars so I just got the rubber ones. There's still some play in it, but not nearly as much.

Blaine B.
November 10th, 2007, 21:53
You just slide them in? No bolts or anything?

mattbred
November 10th, 2007, 22:40
Nay. The transmission mount pushes the transmission up on the front and back of it and leaves the whole middle part of the tranny above the mount. There's nothing holding it there! So all you do is pry the tranny up with a jack+piece of wood, then slide some bushings in there. May have to cut the bushings to fit them in but I HIGHLY reccomend this very simple mod.

Blaine B.
November 10th, 2007, 23:01
Can these bushings fall out? Say if you're a hardcore offroader....

mattbred
November 10th, 2007, 23:09
I wouldn't think so. There's quite the bit of downwards pressure on them. You have to jack up the tranny quite a bit to fit them. Unless something else broke, or the bushings are too small and there isnt any pressure on them, you should be fine. Besides if they ever did fall out, all that would happen is it would return to it's normal (shitty) self.

mattbred
November 10th, 2007, 23:17
On a side note, doing this to stiffen up the driveline should really play a helping hand in prolonging the life in all of the parts in the drivetrain. Motor, tranny, tcase, axle etc. With it bouncing around so easily and jerking, im sure it wouldn't be so good for things.

Blaine B.
November 10th, 2007, 23:20
Ah, I don't have this setup. But it's good to know!

mattbred
November 10th, 2007, 23:28
You don't have a Peugeot?

I'll try and make a write up with pictures tomorrow when I redo it, too!

Harlee&Tahoe
November 11th, 2007, 10:07
2 1/2 weeks with M.O.R.E. engine mounts. HUGE noticable difference I'll take 500rpm vibes anyday. (starting from stop) Wish I could have installed this upgrade a long time ago, didn't realize difference would be so "night & day".

I'm going to try the spacer idea for tranny mount, I looked and seems pretty self explanitory. I have some old skateboard truck poly bushings, hope they fit.

Blaine B.
November 11th, 2007, 10:08
Nopee.

mattbred
November 11th, 2007, 11:07
2 1/2 weeks with M.O.R.E. engine mounts. HUGE noticable difference I'll take 500rpm vibes anyday. (starting from stop) Wish I could have installed this upgrade a long time ago, didn't realize difference would be so "night & day".

I'm going to try the spacer idea for tranny mount, I looked and seems pretty self explanitory. I have some old skateboard truck poly bushings, hope they fit.
So M.O.R.E. mounts fixed your jerkyness pretty much? Also were they torsion rubber or poly? I hear the rubber is much better for vibes.

mattbred
November 11th, 2007, 13:00
Ah crap I totally forgot to take pictures. O well. it seems to help a little bit, it's still more jerky than I'd like. It'll stay this way till I either sell the jeep or get an AX-15 swapped in anyways.

Harlee&Tahoe
November 11th, 2007, 15:38
So M.O.R.E. mounts fixed your jerkyness pretty much? Also were they torsion rubber or poly? I hear the rubber is much better for vibes.

No more clunk at start-up or when I'm driving and hit a bump the trans. used to hit the tunnel. Old tranny mount seemed to be as squishy as the new. After all I heard about poly for this application I don't have dental insurance and want to keep my fillings in place! I went with torsion rubber. Also fixed the jerkiness which I always associated with play in drivetrain. (trans.,u-joints, and R&P in diff.) now when I let off the gas and hit again, instant deceleration/acceleration NO PLAY

Oh yeah now my front driveline no longer hits header down pipe! (Pacesetter)

mattbred
November 11th, 2007, 16:41
No more clunk at start-up or when I'm driving and hit a bump the trans. used to hit the tunnel. Old tranny mount seemed to be as squishy as the new. After all I heard about poly for this application I don't have dental insurance and want to keep my fillings in place! I went with torsion rubber. Also fixed the jerkiness which I always associated with play in drivetrain. (trans.,u-joints, and R&P in diff.) now when I let off the gas and hit again, instant deceleration/acceleration NO PLAY

Oh yeah now my front driveline no longer hits header down pipe! (Pacesetter)
So you got a new peugeot mount? Did you find that it helped? (Did you get it from a jeep dealer?)

The main problem I have is in a torquey gear (first, second and third) if I hit the gas itll jerk a couple times, pretty bad. Same with letting off the gas really quickly. If I let off the gas, then hit the gas, then let off the gas, etc like a swing, the whole jeep feels like it could do a flip and I hear some really bad clunking underneath my feet. Wonder what that is.

praetorian
November 13th, 2007, 18:36
Are you guys running the standard height motor mounts or the one inch raised mounts?

89xj
November 15th, 2007, 04:45
Are you guys running the standard height motor mounts or the one inch raised mounts?

standard.

no need to raise the engine on an xj.