This is my third avalanche, and I have my 3rd broken window frame. It has happened in the same spot on all 3 - right in the middle bottom where the arrow is. It is a known design flaw that has not (possibly can not) been corrected. The 1st 2 times, it happened in the bumper to bumper, and they replaced it. This time, it took 4 years, and the dealer said it is trim, so it probably would not be covered under extended warranty. I probably could have pushed the matter, but I was in a hurry. I'll get the ebay replacement (I think around $150 last time I checked), but I have used RTV to repair it until then. I have a quality dark tint on it, and don't feel like paying for that again as well...