Its time to play: "name that suspension noise"

jwasbury · 10-23-2008, 06:46 AM

The car has started to make a noise which I will describe as a "click" rather than a "clunk." It seems to be coming from the rear, on the driver's side. I can hear it while driving slowly and the rear suspension is working over bumps. It also sometimes makes the noise when driving off from a stop (which I attribute to the fact that the rear suspension may squat a bit during take-off). I can create the noise in the garage by pushing down on the rear bumper.

Last weekend I tried to find the source. Jacked up the rear via the engine until the wheels were airborne, then put some wood blocks under the wheels and lowered her back down. This way, I could squeeze under the car while a friend pushed on the bumper to make the noise. Only problem is, it stopped making the noise. It seems that unloading the rear suspension temporarily made the noise stop...does this provide a clue as to what is going on? I am thinking it might be spring plate bushings. After driving the car on the road, noise is back.

While I was under there, I looked at the CVs (rear axles are new <5k miles on them), sway bar mounts, sway bar bushings (both look fine), drop links, and the rear shock itself (also seems ok).

So who wants to play?

ChkbookMechanic · ChkbookMechanic's Garage

Have you checked the wheel hubs? Grab the wheel near the top on both sides around 11 and 1 and then shake it back and forth. If you hear a clicking noise you probably need a new hub.

jwasbury · 10-23-2008, 07:09 AM

What relationship is there between the hub and the bearings? I had the rear wheel bearing assemblies replaced on both sides (<5k miles ago), not sure if the hub was replaced as part of this. I understand that the 930 has a different set up than the 911. You make a good point though...I need to grab the wheel and check it for play...after the heap of cash that I spent getting the rear bearings done, I don't want to believe that this is the problem (but it could be).

jonbot · 10-23-2008, 01:26 PM

Check for loose bolts, there's not that many to check in the rear end. From my personal experience, make sure the bolts that attach the spring plate to the aluminum banana arm are tight. Good luck!

SteveinTO · 10-24-2008, 09:36 PM

Check the boots on the half shafts for rips and grease leaks. Grab the shaft with car at ride height and see if there's any play. They should move in and out smoothly, but should be pretty tight if you try to rotate them. If the boots rip, that lets grease out & dirt in, making a nice grinding compound to consume the CV joint inner workings.

Also check that the CV mounting bolts are tight.

Also, once had a nail in the tire that made a clicking sound on the street.

jwasbury · 10-25-2008, 08:15 AM

I had new, complete axle assemblies installed this past January. Still, I grabbed on the axles to check for play or try to make the noise. So I'm pretty confident the CVs. It did occur to me that the axle bolts could be loose, and I checked that too...looks good.

Jonbot, I will look at the bolts you have suggested btw the spring plate and trailing arm.

thanks

jacob