mtulett1

i know this may be a dumb question but does an '01 GCL have rear control arms?

SoCalxJ4.0

Does it have rear coils??

dave1123

There are only 3, the bottom two and the top triangulated one. This eliminated the need for a rear track bar. Think coil spring Chevy Chevelle.

mtulett1

yep thats what i have. i think the boomerang shaped one is broken i have a clunking sound back there and i need to fix it. really bad when breaking gently or hitting bumps.

dave1123

It may be just the single point mount on top of the diff. You've been told it's sort of like a trailer hitch ball type thing.

5-90

Probably.

They are required with rear coil springs - leaf springs will locate the axle just fine (fore-aft and side-side) on their own, but coil springs won't properly locate anything - requiring more suspension members.

mtulett1

any idea how to fix that thing?

Mugs

I did mine....kind of a PIA. But doable....without a lift.

But, when I bought my 99 had the same problem. Clunk while going over bumps, etc. Drove me NUTS....replaced the lower control arms...didn't fix the problem. Replaced the Upper Control arm (bushings and ball and socket)...didn't fix the problem. DUH....it was my shocks. THAT fixed the problem.....so before you go replacing all the rear control arms, check your shocks. I jumped the gun I think, but I cannot be sure. I now have all new rear control arms though and new shocks.....ha.
The upper control arm is hard to diagnose because it is hard to get to the ball joint to see if that is the problem. Mine looked OK when I took it apart but I replaced the bushings and ball and socket anyways.....since it was apart.
Could it be your problem?? Sure...it could be a combination of all of them.
The control arms bushings being bad could cause your shocks to go prematurely as well. Good Luck.

I would first get under it with a good light source.....look closely at the bushings on the lower control arms & Upper control arm (triangle shape above the axle). If ALL of the bushings look intact and not touching any metal surface, I would look elsewhere. The upper control arm ball joint is hard to diagnose....and if you go through the trouble of taking it out, replace it anyways. It's tight getting a wrench under there....1/4 turns at a time at best on a couple of the nuts. I remember it being a wicked PIA....I think if I had to do it again, I would pay someone to do it!! Lower control arms were easy....and shocks took me about 10 mins a side!!!

mtulett1

ok thanks a lot! i know this has been like this for years i hit a pot hole and blew out the front tire and the rear shock on the same side. i had replaced both but the clunk was still there. so that is what leads me to believe its the control arm/arms. i'll get under it and see what i can do thanks for your input.

Mugs

Look closely......but when you replace shocks you should replace both rear shocks.....not just one side
My problem (causing the clunk) was a bad shock on ONE side. When I removed the shocks, one side did not expand (broken) the other did...the one shock was basically useless and not absorbing ANYTHING. So...I would verify the other shock is good that you did not replace when you blew the other one out. Believe me, you will thank me if this is the problem. Especially when you go and try to take apart that upper control arm!!!

Also...if you bough the cheapo Auto Zone Shocks, they only last 1 yr!!!!! Check your shocks!!

mtulett1

will do thanks again

mtulett1

lol i'm going to have to buy you some brews if you keep helping me are you close to me? i went and pushed down on each corner of the rear end and the shocks seem to work fine but there was a clunk on the passenger side so i'll have to start there

Mugs

I'm in New England. Not close...otherwise I'd take you up on that offer.

I couldn't tell if my shocks were bad by just pushing on the rear. Jack it up....take the shock out. It should expand. I just don't have a tip for you to get it back in while it's extended (if it's still good).....they come with a plastic piece keeping them contracted so you can get them in....then you cut the plastic piece. If it's bad you'll know....the piston will move freely with little resistance (hence not absording the bumps).
There's could be another way but I have no idea. I'm sure theres a trick to it. I bought Monroe's for like $48 each with a 25% off coupon. Nice shocks.....I got the next beefier size up.
Easy fix if that's the problem.

5-90

Sure there is - go to the suspect corner, bounce it down sharply and let go.

If it rebounds more than three times, or does not taper down the magnitude of rebounds very quickly, you've got a failed shock damper.

Replacement in pairs is a minimum, replacing all four is advised.

dave1123

What he's explaining about the extension is for gas shocks. A gas filled shock comes with a nylon restraint to keep it compressed. A standard shock doesn't. What the gas does is help support the load and becomes firmer the more it's compressed. A good test for bad shocks is a set of railroad tracks. Does it just rumble or does it chatter when going over them? My WJ was up on a hydraulic floor jack in the back and my son released the jack too quickly. It just came down. No rebound at all. I thought "Well. The shocks are still good."