2003 MCS... when the driver's side window is either going up or coming down it makes a squealling noise (best way to describe it). The window has tint on it but so does the passengers side and it doesn't squeal. It sounds like it's coming from the window rubbing on the black velvet-ish window "jam". Any suggestions? Wax the window? The window works smoothly otherwise.

 

Same on my '05 and I have no tint.

 

There are a lot of threads on this I think. Different people suggest different solutions, from lubricating the tracks to replacing the entire mechanism. Everyone seems to agree this sound generally only occurs on hot days, which I will also agree with as it happens to me as well.

 

Take it to the dealer, it is a known issue. Mention that your window motors occasionally stick as well (if it squeaks the motor will eventually not opertate). They will replace the motor mechanisms and fix the squeak no questions asked.