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Discussion Starter #1
When slowly going over uneven surface or road dips where 1 of the 2 wheels has to move down, I hear a very loud "clunk" noise coming from the rear part of the car. :censor: This just happened and I do not know what exactly the problem is.

A quick inspecion shows that the Hotchkis rear sway bar is bolted and in place, no play at all. Car sits evenly with the eibach springs so I don't think it's a broken spring. The rear subframe was inspected 2 days ago and it was fine. :hmm:

What else can it be? I will further investigate when I go back home but I need to know where to look. :banghead::banghead:
 

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your sways are probably hitting the control arms or exhaust pipe when going over uneven surfaces. probably just need to adjust the sway links.
 

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Discussion Starter #3
I adjusted the sways as per Hotchkis recommendation, they are exactly between the control arms and the axle. And I also placed some tape around those surfaces to see if the sways touched but nothing. The noise just started, it wasn't there before! I had the sways for a week and they were fine.
 

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Just Nuts
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Go to the rear of the car and bounce the trunk and see if you can reproduce/locate the noise. You can ask a fat friend for help.
 

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Go to the rear of the car and bounce the trunk and see if you can reproduce/locate the noise. You can ask a fat friend for help.
:werd:

i had the same issue as you, i heard a nasty clunking coming from the rear, turns out the weld on the exhaust hanger broke off and the exhaust was moving around, and when i went over a bump or uneven surface, the exhaust tips hit my bumper making a repetative loud clunking noise from the rear

to check your subframe (if you have an automatic), set your car on an even surface and torque brake until about 2k RPMs (until the car "squats" in the rear) and see if there are any nasty sounds coming from the rear

also, like a previous poster suggested, check your RSMs
 

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When slowly going over uneven surface or road dips where 1 of the 2 wheels has to move down, I hear a very loud "clunk" noise coming from the rear part of the car. :censor: This just happened and I do not know what exactly the problem is.

A quick inspecion shows that the Hotchkis rear sway bar is bolted and in place, no play at all. Car sits evenly with the eibach springs so I don't think it's a broken spring. The rear subframe was inspected 2 days ago and it was fine. :hmm:

What else can it be? I will further investigate when I go back home but I need to know where to look. :banghead::banghead:
Check your bushings (differential and rear trailing arm). If it's not, it could be your shocks depending on how old they are.
 

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May the farts be with you, always
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try going over the same bumps...but with your left feet holding brake pedal held in while you drive through..

it may be the pads that are unsecured and jumping around.. happens alot..
 

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Discussion Starter #14
I found the problem.

The nut came loose (picture below) on the endlink bracket and the endlink was free to move up/down. I couldn't tell when the car was stationary but at road bumps, it was intense. It's a miracle that the small conical fittings that hotchkis provides didn't get lost. I found the nut near the rear spring. So I removed both endlinks, bought a pair of self locking nuts, applied loctite threadlock and tightened them pretty good. Hope nothing like this happens again. I do not know why the nut came loose though, maybe it was not meant to be used again?


 

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Hah, I had a similar problem recently after installing my ASTs. The nut on the lower left side front end-link loosened up ever so slightly causing some crazy clunking noises. As with you, things were fine for a week or more after the install before the nut loosened up. In my case though, the nut didn't come off and even passed a hand check to see if it was loose. It wasn't until I went back and re-torqued it for good measure that I realized it was even loose. Managed to figure it out within a couple of hours but man it was driving me crazy trying to figure out what it was! Good work tracking down the problem!
 

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Hah, I had a similar problem recently after installing my ASTs. The nut on the lower left side front end-link loosened up ever so slightly causing some crazy clunking noises. As with you, things were fine for a week or more after the install before the nut loosened up. In my case though, the nut didn't come off and even passed a hand check to see if it was loose. It wasn't until I went back and re-torqued it for good measure that I realized it was even loose. Managed to figure it out within a couple of hours but man it was driving me crazy trying to figure out what it was! Good work tracking down the problem!
Are you saying it has to be OVER-TIGHTENED during install or at best to use a new nut? Some people are recommending to get new endlinks - which is which? :hi:
 

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Discussion Starter #18
Hah, I had a similar problem recently after installing my ASTs. The nut on the lower left side front end-link loosened up ever so slightly causing some crazy clunking noises. As with you, things were fine for a week or more after the install before the nut loosened up. In my case though, the nut didn't come off and even passed a hand check to see if it was loose. It wasn't until I went back and re-torqued it for good measure that I realized it was even loose. Managed to figure it out within a couple of hours but man it was driving me crazy trying to figure out what it was! Good work tracking down the problem!
Thanks! in your case was the original nut used?
I guess the new self locking nut and threadlock will prevent this from happening again.

Whenever you hear a strange noise it's always worth thinking first about any mods that you may have made.
Yeah, see my first post, the sway passed the first "visual check" but I had to get the car on ramps to further diagnose.
 

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Are you saying it has to be OVER-TIGHTENED during install or at best to use a new nut? Some people are recommending to get new endlinks - which is which? :hi:
in your case was the original nut used?
I guess the new self locking nut and threadlock will prevent this from happening again.
I'm absolutely not suggesting that you over-tighten anything.

Original nut, new end link in my case. It's possible it didn't get properly torqued the first time, maybe the stud on the end link stretched, or maybe it just loosened up. Don't know. They always say it's good practice to go back later and re-torque lug bolts, etc this is probably why.

I re-torqued it and it's been fine ever since. If it ever loosens up again I'll just apply a little Loctite.
 

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I had a similar noise caused by over-tightening my swaybar mounts...the bar could not rotate smoothly in the bushings and would make horrible noises.
 
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