Jeffk

I just bought a 2000 GT with some suspension mods. Springs, aftermarket rear LCA's, stock uppers.

When I take off from a stop I hear a clunk sound coming from the rear suspension. I know on the S197 I would check to make sure the bolt in the UCA was torqued but these cars have what I guess is a 4 link rear suspension on them?

I just figured that I'd hit you guys up since there's a lot of knowledge in here and get some idea of where to start looking. I'm going to jack it up this weekend and see what I find.

Thanks in advance!

Jeff

steel pony

Jeff,

Check the obvious first, u-joints, motor/transmission mounts and axle bearings/bolts.

You're rear setup is a "quad shock" which can be a bit noisy if all of the shocks aren't changed out at the same time, or there is play/slop in the system.
The positioning of the quad shocks (the horizontal ones) can lend to a lot of noise if the those shock mounts are worn or loose.
Check those and make sure there is no play in the mounts or the bushings aren't worn.

Jeffk

I thought I saw 4 shocks back there. That sounds like a pain in the **** to deal with. Time for some more research. lol

Jeffk

Looks like since someone installed upgrade LCA's on this car I can take the quads shocks off! Nice

school boy

depending on miles on the car, it could have some worn parts. like steel pony said, check the obvious first. put the car on jack stands or a lift and start looking and checking for loose bushings, joints, etc. i too would remove the quad shocks since lca's have been changed to aftermarket.

Jeffk

It's a funny noise because there's like a slight sliding sound and then a clunk.

school boy

do the lca's have bushings or heim joints? heim joints are kinda noisy. also, does the rear end feel loose while driving? is the exhaust hitting? anything in the trunk rolling around? lol

TXMach

Is it completely safe to remove the horizontal rear shocks if the upper and lower control arms are upgraded? Are there any potential detrimental effects? I don't know much about suspension geometry.

Jeffk

Trunk is empty. LCA's have bushings. Rear end feels tight when driving. HAHA.
Exhaust is up there and no movement. I wonder if it's the horizontal shocks.If they extend when you accelerate and the ones on my car are shot, couldn't they make noises similar to what I've described?
I'm going to jack it up this weekend and see what I find and take off the horizontal shocks.

Yes from everything I've read on this forum.

steel pony

You are correct!
Those shocks don't do much other than what you have described, and since they are in somewhat of a position to "push & pull" vs. "shock & absorb", any kind of wear or loose fittings will produce noise thru the whole system, thus magnifying your NVH...even if it's off or worn by a CM.

If you can get rid of them, do it...but while you;re at it, make sure you check all of the fittings, bushings and wear on all of the shocks.

At this point, it might be beneficial (if any of them are worn) to just replace the the 2 vertical shocks and uninstall the quads.