Late model window regulators

The mechanism that raises and lowers the window is not called a mechanism, it's called a regulator. If your windows don't move, or move slowly, replace the regulator with a genuine Delco unit from the dealership. The early late models use a nylon gear strip which runs in an L-shaped channel. You really wouldn't want to replace it even if you could. It'll just break again. Really dumb design. Built by the Ferro company, I think, so it is referred to as the Ferro strip regulator. By the way, you can grab the window and pull it up to the top by hand until you get it fixed. It'll even stay shut a while driving until it vibrates down again.

GM will sell you the Delco regulator for a replacement which GM started using sometime after 1986. It is 100% better. You will love it. You should put it in yourself IMHO. It is a metal gear design, real smooth, quiet, and fast. The window will go up and down in 3 seconds instead of the five seconds you're used to. The instructions that come with it are pretty good. While you're in there, if you tape down all the wiring harnesses and tape shut all the slits in the vapor barrier, you can kill all the rattles and drafts. If you've had any leaks it's also pretty easy to adjust the up position of the window to make it seat a little tighter.

The part number is #22063225 for both the left and right sides, although the part number could always change in the future.