I've decided to go ahead and set up an appointment to see what this noise actually is and still in warranty.....

What it does, I hear a "clunk" sound when I hit a dip in the road or an uneven section of pavement. Not always, but always hear it at one part of the road when I leave my house. I heard it again over the weekend when I had to go over a set of speed bumps that were in a V shape. I also noticed that the left front tire seems to lean in slightly at the top. I looked through the TSB's and just didn't find anything that seems to be the same as my issues. Maybe I missed the exact one, don't know. I've had the "clunk" noise for several months now, and really notice it since the swap to the 18" Cobalt wheels.

Thoughts on what this "clunk" sound may be?

Next question, should I swap back to the stock wheels before taking it in? Granted a different wheel set up verses stock, but they are wheels off the delta platform. Problem was there before the swap.

 

may be a busted strut. if it leaks it can cause a simular noise

 

Im guessing it is either the steering column issue or stabilizer end links.
When you hear the noise, try to put your head right beside of the steering wheel, first one side, then the other, and see if it seems to be coming from there.

 

DOn't think it's the column. Sound definately coming from the corners. I hear the sound mostly on the right side it seems. But then I noticed the left tire leaning in just a little more and the left tire is straight up. End links are a possibility, but I also thought of the struts.

 

Mine are my strut mounts. They do it a lot more in colder weather. also my end link make noise.

 

After 6 months of the stupid clunk that came from the front end, I had a local mechanic come to the conclusion that the front stabalizer bar end link was defective, so we replaced it and the clunk is gone!

 

I had a squeek/clunk sound when ever I shifted, came to an abrupt stop, went over bumps and when i shut the doors. Turns out it was a broken recirculatoin vent door.

 

Mine was checked out and they found nothing. Since the weather has warmed back up, it's almost gone. Dunno......

 

i get the same when it is cold, i have no idea what it is yet. it has warmed up and now there is no clunk.

 

My 08 hhr started doing the clunk thing when i went over a bump in the road or over some railroad tracks. I has 28000 miles on it. Took it to the chevy dealer and they said it was something worn in the steering box. They ordered the part and instaled it and the clunk is gone. I wonder after another 28000 miles, im going to have to replace that part again. Oh well, time will tell