First off, I hope this is the right forum for this. Secondly Id like to pose a situation with my power window and see if someone else has had this issue. On the Passenger side only, when the window goes down about 4-6 inches the gears grind and the window stops. Then when you go back up with it it will go all the way up but instead of just stopping it grinds again. Ive taken the door panel off half way and have looked under but can see no obsrtuctions. The grinding is definatley coing from the motor it seems. perhaos there is a switch that stops the motor out of whack? I will eventually pull the whole panel off to get a closer look, as I am going to change the color of the interior from gold to burgandy. I was hoping, though, that someone may have had this issue since it seems alot of problems with F-bodys are common among them all. Sory for the long post. Any help would be appreciated. Its a 1990 RS by the way

 

Sounds like your window motor is going. I just had mine replaced 60 for the motor plus 75 for installation.

 

There is a gear on the motor that mates with a geared sector on the regulator assembly. It sounds like there is a problem with this area. It could be a worn motor, worn gears or worn out pieces causing play when the motor is trying to lift the glass. The glass in 3rd gens is pretty heavy

 

I have the exact same problem!!! Goes down 4 inches, sits there and grinds... goes back up and when at the top grinds again (slower)

I too have taken the whole thing apart, looked all over to see if anything was stopping it, any stuck wires, etc... nothing... i think it's the motor like you guys said, anyone know how hard they are to replace? thanks...

 

Everything on these damn cars is heavy, the hood, the doors the windows....fiberglass is looking pretty good...lol....I figure im in for replacing a winder motor I'll probably let it go till I redo the interior. Ill be using the AC soon enough. Its gettin hot down here. Thnaks for all the replies guys, I figured it was a common issue amongst F-bodies. Ahhh, the things we put up with for our first...er uh second loves (wife is looking at me funny)