I have a 2004 xlr with 20,000 miles on it. No major problems until I put the top down, drove home about 15 miles, and found the small triangular window that was supposed to fold into the trunk sitting on right next to the roll bar behind my head. It had detached from the top as it folded into the trunk Taking it in to the dealership asap, is this a recurring problem?
The adjustment on the "quarter window" is fairly tricky.
I have only had to replace 2 of them.
One was because somebody left something in the trunk when they folded the top, even though he emphatically denies it. I could see the witness marks from the object that he left in the trunk and the damage was quite extensive... but I digress.
The other was because the felt wore off of the weatherstrip and it was making noise. They are easy to replace but hard to adjust.
No it's not "common".