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XJ Wheeler
04-01-2014, 07:21 AM
This is write up on changing out the transmission mount in my '92 Jeep Cherokee 4.0L with AW4 transmission and four wheel drive plus some extra info. For the most part most of the information here applies to the majority of XJs, but not everything. ***The mounts are slighly different on four cylinder models, manual trans, '84-'86 XJs, and '00-'01 Cherokees. So some information may be different for those models. Understandably it may sound daunting disconnecting
the transmission from the crossmember but its actually relatively easy.

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/rk1362-1.gif (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/rk1362-1.gif.html)

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/CIMG39852.jpg (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/CIMG39852.jpg.html)

If you are just looking for the info on changing out the mount skip ahead to "Replacement".

"Figuring out if your mount is bad"

First off, you need to know IF you need to replace that old mount. There is a couple ways to tell, and all require you to get down under the jeep to inspect it. The mount can actually seperate, and what happens is the rubber cracks completely across the whole thing seperating the top and bottom pieces. The relatively simple way of testing for this is to place a jack at the transmission pan with a good sized board to spread the load and lift a little (unless you've eaten
your wheaties and been benching some iron), it will become evident with only a couple inches upward. Its easy to see how this can be a big problem. Another and perhaps the easiest to identify and probably most common problem is the rubber part of the mount getting deteriorated, whether from age or getting soaked in fluids. Like in my case, I have neglected a couple oil leaks and it finds its way back to the mount, soaks in, and degrades the rubber prematurely. Once that happens the mount becomes soft and collapses, as well it becomes too weak to properly hold the shifting and vibrations of the drivetrain. For this i used a big screwdriver, but anything hard you can poke it with should work. It should be hard, such as the tread of a street tire. If not, it will probably be pretty easy to indent the rubber with the screwdriver about a half inch or so.

Here is one of the signs i had of my bad trans mount. Notice how close the exhaust is to the crossmember. The exhaust hanger bracket here bolts in between the trans mount and transmission, the reason it lowers with the mount deteriorating.

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/AviaryPhoto_130380613226452653.png (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/AviaryPhoto_130380613226452653.png.html)

And this photo shows how much the old mount has collapsed compared to the new replacement.

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/CIMG4001.jpg (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/CIMG4001.jpg.html)

"What mount to buy"

So now you should have some idea whether or not you need to get that old mount out to make room for a new one, but what should that new mount be? Stock replacement rubber or aftermarket poly? Now, this decision is mainly based on your opinion, experience, and/or research. On the one hand the stock rubber type mount is cheap, easy to find, and if you search can even find one with a lifetime warranty. In my research i can only find one company that offers a poly mount, Daystar. And they don't offer it for all years so check and see if yours even applies here. Although as jeepers we tend to have the mental battle with replacing with stock and want
to upgrade with bigger and better. So poly would be the "upgrade" and its supposed advantages are longer life and stronger to support heavier components. However, there are a few disadvantages. Higher cost, less availability, and even though its advertised as longer life many have reported short lifespans, some cases less than rubber. In my case, I chose rubber. Mainly because i could go
down to the local auto parts store and get one for a good price with a lifetime warranty.

This is the actual mount i purchased. Anchor #2625
http://www.oreillyauto.com/site/c/detail/ANR0/2625/03234.oap?year=1990&make=Jeep&model=Cherokee&vi=1180011&ck=Search_03234_ANR_1180011_1782&mn=Anchor&mc=ANR&pt=03234&ppt=C0019


"Removal of the Transmission Mount"

Okay, so first you need to grab the tools you're gonna need to do this.
-Floor/Bottle jack with a block of wood
-3/8" Ratchet
-15mm socket
-13mm deep socket
-18mm socket with an extension about 6" long
-Antiseize
-Chalk marker or paint pen, bright color (optional)

Step 1
Take that ratchet with the 13mm deep socket and remove the four bolts from the bottom of the trans mount. They will be located in the center of the crossmember, through four of the holes in the bottom. Don't worry, the drivetrain isn't going anywhere yet.

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/AviaryPhoto_130402139916676052.png (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/AviaryPhoto_130402139916676052.png.html)

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/AviaryPhoto_130380615877959400.png (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/AviaryPhoto_130380615877959400.png.html)

Step 2
The board mentioned in the tool list is to support the rear of the drivetrain so you can lower the crossmember, so it needs to be a little hefty. A typical 2" thick board will do the trick. It is better to have a wider board but since i didn't have any on hand i went with a 4" wide piece. The length is a bit tricky. I definitely recommend long enough to span the entire width of the transmission pan to use the strength of the upright sides, but it can't be too long as the front driveshaft and exhaust are right in the way on either side.

Use the jack with the board placed parallel with the crossmember and snug it up to the transmission pan. I chose to place it toward the front of the pan because its flat there, whereas the pan slopes up in the rear, plus it would be less leverage forced upon the pan to keep from bending it. Now double check that the jack and board are placed correctly and start lifting slowly. You just want to take the weight of the drivetrain off the crossmember so don't over do it!!!

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/CIMG3995.jpg (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/CIMG3995.jpg.html)

Step 3

The 15mm will come into play here. Now, some of your Jeeps are modified and these can sometimes be switched out (as mine had been). But the factory put one 15mm bolt and one 15mm nut holding each side of the crossmember to the corresponding "framerail". So loosen all the hardware here but leave one per side still holding it up and position yourself so you can hold the crossmember while removing the last bolts/nuts. Its not entirely heavy, just a bit bulky. Lower the crossmember and get
it out of the way.

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/AviaryPhoto_130402141684731072.png (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/AviaryPhoto_130402141684731072.png.html)

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/AviaryPhoto_130380616401142567.png (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/AviaryPhoto_130380616401142567.png.html)

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/CIMG4005.jpg (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/CIMG4005.jpg.html)

Step 4

With that crossmember out of the way you can now take out the two 18mm bolts holding on the trans mount to the transmission. If yours is as cruddy as mine you may need
to give a little tap to knock it off.

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/AviaryPhoto_130380623485731240.png (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/AviaryPhoto_130380623485731240.png.html)

And here is another pic of the right bolt to give a little more definition as to the location.

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/AviaryPhoto_130380624237536491.png (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/AviaryPhoto_130380624237536491.png.html)

Once you get the mount off you can now clearly see the exhaust bracket mentioned earlier that is sandwiched between the trans and mount.

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/CIMG4008.jpg (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/CIMG4008.jpg.html)

Step 5 (optional)

Now would be a great time to clean up the area where the trans mount bolts up because the crossmember is normally in the way. Also sprucing up the crossmember itself.
I took the opportunity to paint the crossmember in satin black as well.

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/CIMG4016.jpg (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/CIMG4016.jpg.html)

"Installation"

First off you want to compare the old mount with the new, mainly the bolt pattern. Better now than when you're trying to bolt it up underneath.

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/CIMG4002.jpg (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/CIMG4002.jpg.html)

The installation is pretty much straight forward replacing what you removed, but i have a few notes still.

I don't have the torque specs on hand right now and will be some time till i can get to my FSM so i can't confirm them. They are especially important for the two 18mm
bolts that bolt the mount to the transmission, being aluminum. I have found one source that says 44ft-lbs. for those but again i can't be a hundred percent.

Being very concious about being able to remove problematic bolts in the future i chose to put antiseize on the four nuts/bolts that attach
the crossmember to the frame.

You may have to jack the drivetrain up a bit more when putting the crossmember back in place because the new mount is larger, thus longer.

Also, its just a habit of mine but i like to mark the hardware with either a chalk marker or paint pen. This just gives me piece of mind so i can glimpse at them to see if
any have loosened. I don't have a pic of the actual thing so here is an illustration.

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/AviaryPhoto_130405605814164316.png (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/AviaryPhoto_130405605814164316.png.html)

And one last tip. The trans mount being deteriorated creates more vibration and movement, which can and will wear your motor mounts quicker. So while your hands are still dirty
check those out too.




Once you get it all bolted up and finished... Enjoy the all new enhanced drivetrain stability!


http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/CIMG4026.jpg (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/CIMG4026.jpg.html)

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/CIMG4032.jpg (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/CIMG4032.jpg.html)

...plus the new found clearance.

http://i1108.photobucket.com/albums/h401/xj-wheeler/Write-ups/AviaryPhoto_130380639300287904.png (http://s1108.photobucket.com/user/xj-wheeler/media/Write-ups/AviaryPhoto_130380639300287904.png.html)





There, you just took longer reading about how to do it than it would have taken to actually do the work! :D

FourEyes45
04-01-2014, 03:49 PM
GREAT WRITE UP and Pictures...This is a big help as I need to do mine...
THANKS

abebehrmann
04-01-2014, 03:59 PM
Great write up Jake!

XJ Wheeler
04-01-2014, 07:23 PM
Thanks guys. I tried to get as much info as possible in there.:D

I didn't realize it was going to cut it off part ways through. Can a mod put the next post directly after the original so its continuous and less confusing?

Brasscatz
04-01-2014, 10:30 PM
Thanks guys. I tried to get as much info as possible in there.:D

I didn't realize it was going to cut it off part ways through. Can a mod put the next post directly after the original so its continuous and less confusing?

How about a merger ;)

XJ Wheeler
04-01-2014, 10:42 PM
How about a merger ;)

Perfect! Thanks a lot bro.

Sent via messenger pigeon - i talk, he types.

Steve2kXJ
02-10-2015, 08:50 PM
Had to replace a trans. this week. The two right side 13mm bolts sheared off trying to remove the nuts. (PB or Kroil well) My 2000 XJ cross member bolts directly on the frame via the 15mm, vs. thru those rubber cylinders in your pics. (The front is a stud, the back a threaded bolt hole) Also does the cross member have a front/back orientation that needs to be maintained?

XJ Wheeler
02-10-2015, 10:27 PM
Had to replace a trans. this week. The two right side 13mm bolts sheared off trying to remove the nuts. (PB or Kroil well) My 2000 XJ cross member bolts directly on the frame via the 15mm, vs. thru those rubber cylinders in your pics. (The front is a stud, the back a threaded bolt hole) Also does the cross member have a front/back orientation that needs to be maintained?

Mine had a similar problem when I did the transfer case drop (the cylinder things that go between the frame rail and crossmember) and the studs came loose from inside the frame rail.

Yes, the crossmember is suppose to a certain direction. There is an indent that needs to be positioned toward the rear. Its there as clearance for the exhaust.

6955

JeeperEd
04-15-2017, 03:28 PM
Hey anybody know what size those 18mm bolts are by chance? I need to replace mine and they both fell out on the trail...

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4.3LXJ
04-15-2017, 07:51 PM
If you don't have to get into a nutsert in the frame, you can substitute 9/16" bolts. You will find they fit better anyway.

JeeperEd
04-15-2017, 10:20 PM
If you don't have to get into a nutsert in the frame, you can substitute 9/16" bolts. You will find they fit better anyway.
I'm sorry, I'm not sure I understand? I'm talking about the bolts into the trans housing for the rubber mount in the center of the crossmember, not the outer ones into the uni body...

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4.3LXJ
04-15-2017, 11:13 PM
OK, gotcha. The 18mm thing threw me off

JeeperEd
04-15-2017, 11:24 PM
Yeah last time I tightened them that's the size wrench I had to use.

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4.3LXJ
04-15-2017, 11:28 PM
Unfortunately I don't have any stock Jeeps here right now to pull a bolt and measure. I do have some suspension bolts I can measure. That is as close as I can come right now, and I wouldn't be able to find them until tomorrow.

JeeperEd
04-15-2017, 11:29 PM
No worries, I just need that one bolt. Thanks tho!

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JeeperEd
04-20-2017, 03:00 PM
BTW, it is 12mm/1.75 metric, and anything 40-50mm works in it length-wise.

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