The passenger side window of my 92 Z28 is very slow and frequently stops about 2-3 inches from full close. Then after letting it sit a few minutes it will slowly go all the way up. My question is do I need a new motor for the window? Or is it a dirty track that can be cleaned? If I can find out prior to taking the panel off that would be great. Thanks for any help in advance!

 

Both. The motors are relatively cheap. Clean the track all up and you'll be good to go.

And you'll need to take the door panel off for both.

 

Check the felts at the top of the door.They can be loose when the window is down, but tight when rolled up.They should be adjusted when the window is no more than half way up/down.

 

Well I uncovered my car today and pulled off one door panel. I bought some white lithium grease. Is it worth it to try and clean those window tracks first or just start working the grease into them?

 

If the old grease is part of the problem, I'd make an effort to remove what I could of it.