Transmission Mount

i searched and was unable to find anything good on how to change out a tranny mount. i found some great threads when doing my motor mount. now i want to change out a my tranny mount and also make sure that it is the noise i am hearing.

so if anyone could post some tranny mount info. such as symptoms when its bad, how to test it and how to change it.that would be excellent

thanks
owen

You can only jack up the trans so far (an inch or two) and the shifter or tops of trans hits the floorpan tunnel, if you keep jacking after that your going to break something.

Usually you have remove the whole plate between the trans and the crossmember. Getting it out isn't too bad, it starts to get frustrating putting it back in, taking several attempts until you find the right direction/angle to slide it in and rotate it up so all the bolt holes line up.

Once you have the plate out, its just a couple of bolts to swap out the mount.

I would NOT recommend dropping the crossmember to swap out the trans mount. From what I read and what it looks like, pulling the bolts for the crossmember can be a royal pain as well as likely to snap creating far more work.

Ive been looking at changing mine as well, learned a few things that might help. I still have questions myself.

Like Rick said, leaving the crossmember attached is safer. I was about to do this the hard way and drop the crossmember, so I tested all 4 fasteners on mine, and they turned easily. But I decided to put off the job after I discovered my mount was still good, the rattling noise was the damned exhaust hitting the crossmember from a sagged catalytic converter mount. I just jacked the cat inlet flange up and bent the whole mess upward an inch, no more rattles.

The AW4 mount's rubber cushion has a inverted v shape, and there should be a gap beneath the peak of the V. My mount has collapsed but not torn, over bumps the shift lever is stable, and there's no banging from the trans tunnel. You can test it by prying inside the gap, looking for excessive movement.

The question is, after raising it with a floor jack, where is the safest place to support the transmission? I've seen a jackstand placed on the output shaft of the transfer case, or the double cardan, but it can't be good for the sloppy old things. The other spot I've seen a jackstand placed is the "belly' of the transfer case, which doesnt seem flat enough to trust.

The AW4 has a cable shifter, does it NOT? I think, don't know, that only the manuals have shifters that are actually attached to the trans that would relay motion of the trans. I know my AX-5 shifter was telling me the driver's side motor mount was torn in half. Any acceleration greater than moderate would result in the entire shifter swinging toward the passenger by 2".

I would not jack up on the trans pan, it would likely dent or collapse. Nor would I jack up on the very end by the output shaft. Anyplace that is solid/structural and flat should be good, do not put too much force on it, i.e. top of trans pressing against floorpan, or you can do damage.

Using Jackstands to support the trans? Problem with that, most jackstands only adjust one inch at a time, and you need every inch you can get. To use a jackstand you have to lower the trans down on it and give up some space you need.

The Crossmember will protect you and Engine/Trans if the Floor Jack should collapse. I just used the Floor Jack because of this. It only takes a 1/2 hour, and its not that heavy with the leverage, so its not too stressful on the floor jack. Remember, you can get away with this SAFELY, because the crossmember will catch everything if the Floor Jack Collapses, that not the case with other things you jack up, never get under anything that is NOT supported by Jack STANDS. Several people a year die when rely on just the Jack to support a heavy object they crawl under and the Jack Collapses.

I just replaced my tranny mount last weekend. used a floor jack under the tranny with a long piece of wood to spread the weight. No jack stand.
Undo the 4 tranny mount nuts inside the cross member, raise the tranny a bit, undo the 2 18mm nuts on the mount plate, raise tranny a little more. remove tranny mount plate, remove tranny mount, replace tranny mount, replace tranny mount plate, insert bolts, lower tranny, install 4 trannny mount nuts inside cross member.

20 minutes, tops.

DaffyXJ said:

...Undo the 4 tranny mount nuts inside the cross member, raise the tranny a bit, undo the 2 18mm nuts on the mount plate, raise tranny a little more. remove tranny mount plate, remove tranny mount, replace tranny mount, replace tranny mount plate, insert bolts, lower tranny, install 4 trannny mount nuts inside cross member...

Click to expand...

Thanks DaffyXJ, that jogged my memory, it was easier to remove and re-intall the trans plate if you leave the nuts attaching the trans mount to the plate loose, so you can move the two around a bit as you try to get both out or in together. The trans mount has to come out and go back in with the plate, there is just not enough room in between the crossmember and the trans plate to clear the studs extending out of the trans mount.

There is a rubber ehxaust hanger that attaches to the crossmember as well. It is held on by four rivets. All of the rivets were broken on mine. I replaced them with bolts while swapping in a new Daystar poly tranny mount and all is right with the world. No rattles. Also shifts into 4WD much easier now.

Hey I just replaced my TM as well, is was a little beat. I was hoping to stop a klunking/rattling I have when going over bumps. I removed the crossmember, it looked hard to do without. Used jack/stands. When installing the TM, one sides didn't seems to fit snug, it just didn't line up, like the part didnt fit. I just tightened it as much as possible and put it all back to together. Found two of my crossmember bolts spinning, wouldn't tighten. AArg! So I pull up my carpets and what do I find? Holes already drilled in the floorpan with round plugs sealing them. They are right above the bolt holes! Genius! Pop them out, drop a bolt in and put a nut on the underside. Keep an eye out for these holes, what a little lifesasver.

Of course, I still have my klunk/rattle.

it is a Jeep, after all.

- TJ