Mugs

I have a loud "thump: in the rear when going over bumps. Had someone look at it briefly and they said it was Rear Lower Control arms. I had the rear lower control arms replaced.....still have the problem. The shocks don't look bad but probably could be replaced....but I'm curious about the Upper Control arm. I will inspect the bushings but if it's bad, what should I expect to find? How can I inspect the bushings and the ball joint assembly without removing them? I see the Control arm only has 3 bushings (they look OK)...the whole assembly costs $100....Would it be wiser to replace the whole unit or smarter to just replace the bushings. If the bushings don't look too bad I would assume that the Ball Joint is the culprit. Trying to save myself a few bucks here....since I am constantly replacing parts on this JGC (and I'm sure I will be able to contribute my findings and mistakes here). I do all the work myself for the most part but the suspension parts are tough to do on my back in my driveway. I have a tough time justifying paying someone to do it for me....unless I don't think I can do it myself.

PatriotGT

The only thing hard about changing the bushings yourself is getting
the old ones out and pressing the new ones in. I just replaced mine,
too cheap to buy the unit, so I just got the parts (2 busings and 1 balljoint)
from Rock Auto for $50 including shipping, but I do have a press.
Should be easy just swapping in another unit.
Place the jeep on stands, not under the axle assembly, use a floor jack under
the axle center. Remove the bolts in the bushings and remove the 3 bolts holding
the balljoint to the housing. Lower the housing so you can remove the upper arm.
I put the 3 bolts back on the housing first (loosely) then used the floor jack to raise
and position the outer bushings. Then tighten everything down.
There are a couple of other fittings you'll have to remove first, but they should be
obivious.
note: mine still bumps hard when hitting a bump. Check your bumpstops, mine are gone, letting the shocks bottom out, thus causing the noise.

Mugs

Excellent....I will check the bump stops first. Thank you for your reply.
Also, I have access to an Arbor Press...would this suffice in pressing the old bushings out? Or would I need some pneumatic type press? I do have access to both. But, I am hoping it is bumpstops vs. Upper Control arm.

PatriotGT

not sure about the arbor press, mines hydraulic. Bumpstops are about $22 each
x 4 (in my case) = $88. while the bushings & balljoint were $50. Now I'm fairly
certain I've blown my shocks. At least they have a lt warranty.

Mugs

I am tackleing this job this afternoon....I did see a tip that said do not jack up the rear end when tightening bolts, thus putting a preload on the bushings which can cause premature wear?
It looks as though I will need to jack the rear end to remove and install the Control arm itself.....yet, when I tighten the bolts the RE will need to be free from the jack.
I did lubricate all the nuts and bolts last weekend and I was able to break them all free. That's half the battle.
The other battle will be removing the bushings....I am curious as to how they will come out and the new ones will install. I have access to a press (a couple miles away) but will try other means to remove them first.

BTW, my bumpstops are fully intact.

Mugs

If someone does a search on this I hope they read this....

The bolts mounted to the rear end have lock-tite. Those babies are in there. Took a good hour with limited room to get them out. Once they were out the control arm came out no problem. If your replacing just the bushings you can hammer them out. Use a press to press the new ones back in.....is it possible to do without a press? I think so. Hammer the old ones out...you won't brake anything.
Attach the new ball joint to the control arm BEFORE putting the control arm back in and slip the bolts into the holes. It will take some manuvering to get it alinged. Tough to start the ball joint bolts.....probably took us the longest time. Once started we were able to get the assembly all back in.....probably a 2 hour job if you don't have a problem with the bushings. You have limited room for the ball joint bolts....no room for a socket. Wrench is all you can do.....1/4 turns...and a lot of them with lock tite bolts. SUCKS.....but it's do able. PIA job but worth it....less banging in the rear butt I think I need shocks too....those will be replaced this weekend. Already did rear lower control arms.....can't be anyting else. WTF. 150K miles and the rear suspension is completely new. WTF

Redbarnrick

I just did mine over the weekend, this may help the next person. Place the car on jackstands in front of the lower contol arms on the frame, you can stack 3- 2x12 wood blocks under the jackstands for extra height, just make sure they are stacked neatly, I used ramps on the front end to raise the GC level front and rear. Remove all the lines first then the bushing bolts, the ball joint stud has to be broke loose, ( a special puller is required, I didn't have one and none of my pullers would work) I inserted a splitting wedge (for firewwood) in between the contol arm underside and the top of the pumpkin, careful there is a brake line running thru that area. I put the nut back on and lowered the diff. a bit to gain some room and from the side with a 1 lb. hammer I wailed on the nut untill the stud came loose, the wedge made it solid as I hammered on the stud nut. I also tried to remove the bolts from the ball joint before l got the control arm loose, with the loctite on it it was near impossible to wrench those bolts out, I loosened all three then squirted laquer thinner onto the bolts to soften the loctite, but I found once the control arm was removed there was room to get an impact wrench and socket in there, once I removed the ball joint i was tempted to try your method but the ball joint bolts are torqued to 100 lbs. so I knew I wasn't going to wrench them in with the ball joint already attached to the arm. I installed the ball joint with new loctite and the impact wrench then torqued them down, I installed the new control arm ( old one was too rusted to reuse) and left the bushing bolts loose, after a couple of attempts at lining up the contol arm and the ball joint stud, I realized that I was twisting the differential forward jacking from under the pumpkin at the rear cover plate, I moved the jack and a block of 4x4 to the front of the diff under the input shaft where it angles up toward the yoke, by jacking there it raised the diff. at the proper angle to get the stud lined up and the nut on. I found that I still had to use two wrenches one on the nut and a 10 mm wrench on the stud to get the taper to seat so it wouldn't spin, once I got it to seat I lowered the diff. to get the impact wrench on the ball joint nut and got it tight. Once the balljoint was tight I raised the diff again to ride height then tightened the bushing bolts, the rest went easy. One more thing I did was to replace the exhaust rubber hanger on the tailpipe $2 and worth it. No noises or thumps even on a bumpy road.