I can see lines in the window, and my finger catches the groove. It appears to be rubbing something inside, but what?? Mine is an 06 GT. Do any of the other years do the same thing??  Thanks Dennis  

the problem is from the inside window seal being made from hard rubber.  You need to buy the window tint protector kit called " Moleskin".  I can't remember if they are the manufacturer or if moleskin is the product name.  Anyway, the moleskin is a soft felt strip that you stick on the inside window seal.  The kit I bought was $30 and I did both windows in no time.  I only wish that I new about it before I tinted my windows.  If you can't find it on the net, reply back and I'll get the address for you.  Hope this helps.  

The very same thing happened to me, however, the "moleskin" was installed...just poorly. My issue was that I tinted the windows in the summer and the driver's side felt peeled off due to the heat softening the glue. The passenger side is still fine.