Issue:
Over the last few years I've been hearing a clunking / rattling sound from my right rear suspension. It sounded like something was very loose, and almost like metal clanking on metal. It was super annoying and made the car sound cheap. The noise was increasingly noticeable in cold temperatures (Fall / Winter) and completely gone in warm temperatures (Spring / Summer). Clearly the expansion and contraction of whatever was rattling made a big difference.

Diagnosis:
I installed an H&R Street Coilover Kit almost 20,000 miles ago, so I figured one of my rear shocks were on their way out, but I wanted to start with the cheapest solution first. I did some digging and read that the sway bar endlinks were common to go and I was planning on replacing those anyways with adjustable Powergrid links, so I did that. The problem persisted. Next was the lower control arms. I read that the bushings on those go after a while and again, I was planning on replacing these anyways (needed to adjust my camber based on the lower ride height), but that still didn't solve the problem. I noticed a little play in my H&R rear sway bar, so tried re-tightening all the bolts mounting that, but it didn't help. Finally, I replaced the entire suspension with a new set of H&R Street Coilovers, confident this would be the nail in the coffin. STILL, the noise persisted. What the *****? I consulted my Dad, a retired mechanic and we went back over everything, tightening anything we could get a possible turn from.

Solution:
I had used a large breaker bar to tighten the (2) bolts that mount the top of the strut tower to the car. This, as it turned out, was the problem. Even though it felt very tight, especially with the leverage of a 24" bar, there's a big difference between leverage and shock. We went back over those bolts with an impact gun and got a couple more turns from both of these. The noise was FINALLY GONE. That small amount more tightening made the difference. It's deceiving because the clunking / rattling sounds like something very loose, when it's actually something tight but still has the smallest amount of play.

 

Thank you so much for that information. I have been dealing with this cold weather issue for two years. Thanks for sharing this information. Ill get these cranked on today. Now do you know a cause for the 2004 S pulling to right. Have tires, wheels checked and alignment. Coil-overs, front control arm bushings, rear sway bar fairly new. Also steering wheel doing the bump steer, I think that's the term, back and forth on uneven surface or bump. Any help would be appreciated.

 

Thanks for the info. Great post !

 

Tightened mounting bolts on coil overs. Still have some clunk though. Looking at a tightening issue I'm sure. Maybe air gun wasn't strong enough, what do I know.

 

I'm guessing all bolts were tightened to spec with a torque wrench?