242xj

Hello all. Been working on the Jeep I bought a few months back. I've replaced the floor pans with some 16 ga steel sheet metal, new hard brake lines to/in the rear, new tires, battery, speakers, etc. That's all gone decently enough for working in the cold with not quite enough space or tools. However, there has been a clunking sound when under acceleration from a stop, or heavy acceleration at low speeds.

So this led me to replace the transmission mount. The old one seemed fine, so motor mounts it is. The drivers side is shot, and the passenger side is completely fine. The motor mount on the passenger side sheared all 3 bolts off, though. Makes sense why lining up the transmission crossmember was much worse than anticipated.

I bought Ironman 4x4 Fab motor mount brackets and am starting on the passenger side. For the life of me, I cannot get it into place. The "ears" that holds the motor mount sits level with the bottom of the motor mount itself (where the bottom of the motor mount would touch the bracket attaching to the body/frame). No manner of jacking the motor up/down seems to make a difference. Any tips for this?

Side note. How bad would it be to use the 5 other holes and not the 3 original ones? I'd like to get the old bolts out, but I'm not sure I have the tools or capability in my garage. I don't off-road at all and am stock height, no lift or anything.

lawsoncl

Greased the slip joint at the front of the rear driveshaft yet?

242xj

Not yet, I didn't even know about doing that. Thank you for the tip.

vroomvroom

When I replaced my motor mounts, they were a pain. I went ahead and got Brown Dog poly mounts. They are strong and a bit noisy, but my XJ isn't my daily.

Anyways, I remember having a tough time as well. I believe I replaced both motor mounts and the tranny mount at the same time. It is easier to align the motor mounts when the tranny mount is off and you have a block of wood and a jack supporting it. You can lower the jack some or raise the jack some or slightly shift everything. I imagine most people here are only using the original 3 bolt holes instead of the more heavy duty bracket that uses 7 holes on one side and 8 holes on the other.

Our Jeeps are old and probably have crud inside a lot of these bolt holes. I would run a thread chaser (some companies call it a thread restorer) to clean the threads and an air nozzle on a compressor as well to get anything out of the holes.

Sorry I'm not much help! I hope you are able to get it!

BillyBoy

First, (Lawsoncl) Vets on the site, please quit leaving sarcastic, what you think are "funny," comments or advice for our New Users... it makes us look bad.

Second, I hope you didn't take his advice seriously, as it has no bearing on fitting the engine mounts in the steel enginge-bay mounts easily or correctly.

When working in the cold, its a whole different world. Things swell and dont fit.

What I did, and it seems rather crude, is "Love Tapped" the ears of the mounting brackets, evenly (both sides) with a 3 pound "persuasion device." ( hammer.)

Now, you're going to think, how can I do this? The hammer won't fit between the brackets....

Use a prybar, or even a long extension for a socket, to go in the hole, and "tap" it. Over and over...

You don't want to mangle and bend them, but a little outward bend, whatever tool you use will help out.

You need only a centimeter or 2, and they will squeeze back into place with the mounting bolts.

Please remember, once the bolts are in, to take the lift/holist/jacks OFF of the engine, so it can sit "Naturally" BEFORE you put the final tightness to the mount nuts and bolts. If you tighten them BEFORE you "Rest" it, it'll bind and want to move.

In ending, it's not that easy to move around a 400lb engine, especially with the trans attached. It's usually a 2 person job, with alot of swearing and jostling involved. If it was EASY, everyone would be doing it, instead of paying a Mechanic Place 500$.

Prybars, possibly Socket Extensions, to Hit with a hammer, to widen out those tabs, with "Persuasion" and then squeezing them back together the .5 inch is the way to go.

Good Luck, God Bless.

BillyBoy

Also, for anyone reading this, replacing ALL THREE, (2 Motor mounts, and the Trans mount) ALL at the SAME time is the way to go. They all work together, to hold your drive train in place... chances are, if one is shot, the others have been "making up the difference" and are Severly worn by the time you notice...
also, Visual Inspection doesn't usually work. These parts may "Look" good, but when you pull them, they are degraded.

I.E. ("In Essence")...
If you change Only the trans mount, or Only the engine mounts, chances are, you'll still have the same problems/"klunk."

If youre committing to the Project, it only costs a lill bit more, both in time and money. Although, i would recommend NAPA parts... i usually go AZone or O'REILLY, but it seems the NAPA or specialized Aftermarket ones work best.

Put them in, tighten them down, reasonably tight, and then,
make sure, AGAIN, to only tighten them for the Final Time, when they are in a "Resting" position. All three.



Good Luck. God Bless. ​​​​

Old Man Minimalist

Man, you have me nervous now in changing my motor mounts. I am replacing all three, starting with the trans mount since I dropped the crossmember to be able to adequately clean the crossmember inside and out as well as the transmission/transfer case.

I was thinking/hoping that I could change one motor mount out at a time. Orient/jack the engine enough to remove the bolts, slide the new motor mount in place, replace the bolts and tighten loosely, then do the other.

Sounds like maybe not.

BillyBoy

Sorry, not trying to make it seem intimidating. It's a one day project, preferably with a "Helper," depending on how much beer he has consumed.



Really, you can do the whole thing with just a car-jack, although 2 would save you some time. Doing all 3 mounts at the same time, is Definetly the way to go. Spend some effort and spray down the nuts and bolts a few separate times, in the days prior to tackling it. PB Blaster, WD40, etc... your choice.

The trans mount, although a bit dirty, if you live in Michigan, isn't really an issue, although, again, you want to "float" the bolts, and only have everything thru, and nuts on, in place AFTER you have the motor mounts lined up. That way, you can Wiggle and persuade the engine in place, and the mounts where they need to be.

Picture it... you replace a nice firm Trans mount, then go up front to your engine bay, Loosen those bolts, jack up the engine, even only an inch, to take the weight off the engine mount bolts... what are you doing to the New Trans mount? By having everything loose at one time, you save a lot of headache. I always have to raise my engine about 3 inches, to "Love Tap" those tabs a Little more wider, so the mounts slide in. Again, also, please have a prybar or extensions for doing so, as well as for using to Tilt and move your motor to get the engine mounts lined up. An Enging hoist isn't necessary, just be sure to out a piece of wood on your jack, to NOT Damage the Oil Pan, or wherever you choose to put the weight.

And, finally, the MOST important part, only give them their Final Tightening, when the jacks are removed, (bolts in place, resting the weight on the bolts) and THEN give them their final tightening up. I used weak strength Lock-Tite, althought it isn't necessary.

If the weight in place, you will get rid of that "Klunk." If you tighten them, when the Jack's are holding the weight, it'll be unpredictable when they settle in while you are driving.

All-in-all, I did it by myself, a few times, didn't hurry, and was done in a day. A few different prybars from Harbor Freight ($15) a 3 pound small hammer, a car jack (preferrably two), some PB Blaster, a 12 pack of PBR, and some planning is all you need. Buy a case of the PBR if you plan on enlisting some help...

And PLEASE, PLEASE, PLEASE, keep your fingers out of the way, when lowering the jacks or shifting the engine!!!
"Chicks Dig Scars, they Don't Dig Nubbins...."



Good Luck. God Bless.

Old Man Minimalist

Sounds good. I am fortunate that my Jeep is rust free so bolts should come out fine. I was even thinking of unbolting the brackets from the block so I could clean them up and paint them. They have just a touch of surface rust on the "ears" and I am being fanatical about removing ALL rust from this Jeep.lol.

242xj

I appreciate any tips. I did loosen the tranny mount, but I think I may just take it off again to see if that helps. Plus, the exhaust rubber mount over the transmission crossmember is in pieces. I'll probably try to rig something better up to keep that in place while the transmission mount is off again.

The 3 original bolt holes have the broken bolts off in it still, just under flush with the motor. I have reverse drill bits, but am trying to figure out if I can get the drill in there at all. I will try though!

I did take the advice seriously. I wasn't sure how it would help so I did a search and came up with this thread here https://www.cherokeeforum.com/f2/how...erokee-242834/ I saw that having a dry slip yolk could also cause shuddering in that thread. So, while I didn't understand how it would help with the motor/trans mount installs I did see how this could be another area of concern. I do believe I will work to get the mounts all in first and see how the Jeep drives then, and go from there.

That's some great advice! I did seem like it was close, so I will give that a try once I gear up for the cold (how's this snow doin' ya in Michigan today?)

I will make sure to do a final fit/tightening with the natural sit of the Jeep on the ground. Thank you for the reminder, as I'm not looking for any new issues (especially caused by my own doing).

I did have plans to do all 3 mounts at the same time. My mistake was doing the transmission mount before noticing the motor mount bracket was sheared off on the passengers side. Then I needed to wait for the motor mount brackets to come in the mail. I can see how the new transmission mount would be hurt from driving a week without new motor mounts. If I have to replace it again I will, but would likely go with a better than stock mount. Same with motor mounts, when they go again in the future.

So, to add to your advice... check all the mounts on the vehicle before starting replacement. If a bracket is broken off the engine, get that part ready before starting so all 3 mounts can be done at the same time.

I think my case might be a little worse than some. If I didn't have to replace the motor mount bracket itself, I think it would have been much more manageable. I do believe changing one motor mount at a time is the correct way to do this, starting with the drivers side if you have a choice. Although I did read and hear that, I can't say for sure the reasoning or validity behind starting with the drivers side.

I wouldn't be overly put off because of my issues. I don't believe it will be easy to do the motor mounts in your case, but I think it'll be easier/more manageable.

Bets of luck!

242xj

I have loosened the 4 bolts holding the mount itself, but not the crossmember bolts. I was worried because I had to shift the crossmember so much when trying to get it in, but I'm not over loosening those since it wasn't all that bad in reality. I have a 3 lb hammer that made the shifting possible, so I will use that for the other areas you mentioned.

Adding on to your advice again, yes please watch those fingers when moving anything with weight/pinch potential. When I removed my transmission mount crossmember I did not know of the broken motor mount bracket. I watched videos and at least one person suggested using a jack-stand to support the first side taken off. So when the opposite side bolts are removed, it won't drop super hard. They didn't know how heavy it was, and from their reaction it wasn't that heavy. I did place the jack, but didn't realize the motor wasn't supported on one of the motor mounts anymore from the broken bracket, and the crossmember shot down really hard when removing the last bolt. I smacked my hand and arm into the concrete between the crossmember. Thankfully no lasting damage to me, but I consider myself lucky and that's not a place I want to test my luck. I was at least smart enough to keep my head and body out of the way, knowing a few stories that didn't end so well for people who have worked on their cars before.

I have some old Hamm's around that I might need to crack into today lol. So much has gone wrong in life since buying this Jeep that I'm a bit tight on cash, and I need this vehicle to work again to make ends meet. So cheeeeeeap beer and some swearing coming up. I'll report back later tonight with what I have, or have not accomplished.

Thank you again, for all the advice. As a newbie to Jeeps, this is a big help.

Edit: When I said 'not over loosening" I meant to imply I am not above having to beat the transmission crossmember into place again. I re-read and realized my choice of wording was not great.

Old Man Minimalist

Well, I have been looking for some OEM motor mounts or equiv. and so far I'm striking out. I can't find any OE mounts and all the aftermarket offerings seem to have poor reviews. At this point, I might be better off with my factory mounts with 200K miles on them vs buying the cheap Chinese versions.

Not really interested in Brown Dogs as I want to minimize any NVH in the vehicle, not enhance it.

242xj

I went on Rock Auto and got some for 5 or 6 bucks a pop. Looks like the ones that came off, but no guarantee mine were original. https://www.rockauto.com/en/catalog/...tor+mount,5552 is where I found mine, but again I can't guarantee any quality on them. They are cheap, though.

lawsoncl

I posted that in response to OP stating " However, there has been a clunking sound when under acceleration from a stop, or heavy acceleration at low speeds.", which can often be the slip joint.

Guess I should have quoted that part of the original post, so it wouldn't get taken out of context.

242xj

All good from my end, lawsoncl! I appreciate the extra information from you on what other areas could cause the problem I am experiencing, as well as the other helpful points brought up in this thread. It's all new to me, and anything I can learn on problem areas are a big help.