The "Move to a warmer climate" mod has a tendancy to fix this as well. You might have to replace the rear defroster, but replacing whole rear window would be easier. Each case it will cost a bunch.

Another fix that has worked for me is to replace the head unit with a stereo that has a screen, remove the trunk key entry and replace it with a backup camera. I haven't had to deal with any problems with seeing behind me since.

Actually I would slowly inspect each of the bottom leads to make sure they aren't broken or damaged.

 

The dealer has already changed the rear window.
I completely inspected this glass and the surface mount of the defroster element, and its fine.

Since wiz kiddsaid he hears about this a lot, I'm going to accept that this is a bad rear window defroster design, looks like one. I hope that is the only poor design in the car. What would be cool is if someone made rear glass with a good defroster design for this car and I could make GM buy me one under my GMPP.

04 Intimidator,Did you really have had to put a camera in the truck to see behind you?

2000LS, The heated_garage_mod would be nice, but what iffog generates on the rear windowbecause of weather conditions, that mod wont fix everything and would be too expensive, will GM pay the gas bill?