I have a 2004 Avalache that is leaking water into the rear and front passenger side carpets as well as a small amount into the driver's rear side during all rain storms. The leak is coming from back tailgate area. I have blown all drains out with air compressor - no clogs. I have removed the rear window twice since I owned vehicle. Chevy dealership is trying to say that leak is from heavy usage and incorrect assembly when putting window/midgate bar back into place. We used owner's manual to reassemble and the parts clip into place - not much room for error. Dealership wants $900.00 to replace all the rear seals in the entire back bed area. Called Chevy and waiting for reply. To add insult to injury, the dealership states there is no guaratee with the job and if I remove back window again and install "incorrectly' they will charge another $900.00 to fix again. Also, they charged $82.00 to find the leaking problem even though I had identified it for them and left my truck with more water in it than when I drove it in. Has anyone else experienced similar trouble? Any quick fix solutions? Another friend with the same problem siliconed his back window and gate shut.? Why hasn't Chevy mandated a recall? Any help appreciated!