I live in NY so I have snows on the stock rims and the originals on alloys. Now I switch twice a year myself, and torque myself. The first time was with the originals still on stock rims.My dealer always uses an impact wrench set to 1 million ft-lbs., so no chance of being loose. Just don't have a flat out in the boonies. I bitch them out constantly about it. However, when I did my own brakes this time, I noticed a loose lug on the suspected warped side. I neglected to re-torque after 25 miles or so this spring when i switched. Also, after the first time, they said there was a TSB out about it. I used ceramic pads and 2 year warranty rotors from Autozone so we'll see how it works out.
I have replaced my rotors once abnd i figured out why recently, the tire store where I got new tires at did not torque the front wheels down correctly and it warped the rotors. After I replaced them and torqued them down correctly my vibration was gone, until the next time I had the tires rotated at the same place, the vibration came back a few days later and now I have another set of warped rotors... i am just living with it for now but know i will have to replace them again... No vehicle of mine will go back to that tire place again... did you notice your vibrations after the tire rotations?
My HHR is an '07 as well, an LS model. To answer your question, no, nothing like that, but I only have 23k miles on it. However I just put the 3rd set of front brakes and rotors on it due to bad vibration from a warped rotor. The first 2 sets were done under warranty, but unfortunately the 3rd set I had to do because it went past the 12k/12mo cutoff for the repair. Happens about every 10K miles. Experience anything like that? Your clunk may be a result of your accident or it may be that I haven't put enough miles on yet.