I was plagued with suspension noises last fall that have finally been fixed. I thought I'd share with you all what the problem turned out to be. The sway bar bushings (front and back) were the culprits. An application of waterproof silicone grease solved the problem. In tracing the problem I had Tarett Engineering supplied rubber boots installed on the drop link bushings. Although the drop links weren't the source of the noises, it was an elegant solution to a non problem. I would recommend these boots to prevent wear on the drop link bushings, if you drive in rainy/dusty conditions.

 

I can't imagine how rubber bushings could make noise that you would notice.

Were these the stock bushings? Did you undo the sway bars to apply the grease inside the bushings or did you just smear it around the bushings?

 

Is your suspension stock and what did the noises sound like? Occasionally i get a clunk from the front end but think it may just be the gt3 lower contol arms and the camber set up but am not sure. P dealer had a quick check last time car was in but says all is fine, nothing loose etc.

 

Wow Larry who would have thought. That bushing looks like some silicone material?

A reminder of how frustrating and tedious problems with modding could be (had this been stock, we would have dropped the car at the dealer with the instruction "fix it"), and the importance of having a good tuner.

 

Since the sway bars are H&R and a thicker diameter the bushings wouldn't be stock. Since I didn't do the work, I can't say for sure what was entailed, but it only took about an hour of shop time. Just smearing grease around the bushing wouldn't have done much. The problem ("binding") was discovered when the bar was disconnected from the suspension and then moved up and down. I guess you could assume the binding would increase when the bushings would heat up after driving some distance in warm weather.

This was a hard problem to pin point, since the noises usually occurred only during warm weather (which we don't get much of here) and after the suspension "warmed up". This made it hard to reproduce the noises for a shop technician. When people ask what did it sound like, I can only say it sounded like the car was coming apart at the seams. More annoying than anything else.

I'm not sure if this was due to an improper installation or not, but my tech didn't charge me for the work, so I'm happy.

 

My RSS sway's used the stock bushing so the H&R could also re-use the stock bushings. It's academic anyway.

Glad you resolved the problem. It's definitely a strange one.

 

good post...thanks!

 

BUT WAIT! There is more. I just got back from a 1800 mile trip to the bay area via back roads. The noises are back in spades. I mean now it sounds as if the front end of the car is coming apart. Fortunately I was able to get one of my dealer's techs to ride with me in their parking lot while it was making all these weird noises. They think they have diagnosed the problem and I take the car in for repair this Thursday. None of the other "fixes" solved the problem.

I will post the next chapter of this saga after I get my car back from the shop.

 

The droplinks would be my bet.

 

The latest suspect for suspension noises is the upper strut bearing. The mechanic found dirt and sand contaminating the bearing. He cleaned it up and lubricated it, and said that should do it. Removing and replacing the bearing would entail taking apart the suspension and a realignment.
WE SHALL SEE IF THIS FINALLY CURES THE PROBLEM.

The service adviser said both turbo's and GT 3's are subject to this problem. Seems strange to me that Porsche wouldn't have designed better protection for preventing contaminants from getting into the bearing.

 

Good info but dont know how a bearing can be pssoibly rid of sand dirt and grit without being removed. That stuff hides everywhere in a bearing. Usually you need to submerse the bearing in a cleaning fluid and then blow it out with an air gun. Plus once a bearing has been exposed to those abrasives its never the same.

 

I know this might sound elementary, but maybe it could be your dampers? Have you looked at that? Maybe putting it on a shock dyno?

 

Thank you all for your inputs. First to properly clean the bearing may require its' removal, but if I were to do that it would make more sense to just replace it. Either way would require an alignment when the suspension was put back together. No one here suspects the shock absorbers themselves. (We have three cars here in the Seattle area all exhibiting the same symptoms with mileages ranging from 24K to 52K.)

 

I have an identical problem to Larry's because mine is his Cobalt twin. I spoke with the service advisor at our dealership and he went further in telling me that the noises might have been magnified because of the fact that the aftermarket Bilstein coilovers uses aluminum mounting points as opposed to steel ones like the OEM setup. As Larry said, the noises exist in GT3's, etc but not to the degree in which we'd both been hearing. I also started experiencing the same noises after the very same 1800 mile (although mine was 2700 miles) trip that Larry went on. I'm taking mine in next week and I hope that cleaning/lubricating the mounts fixes the issues too.

 

Speed, what is your suspension setup? I was thinking of moving to GT2/3 control arms etc as well. Please share your thoughts.