I made a recent return to the service dept to get my Buick transmission repaired under warranty. If you haven't had a warranty major problem it now requires GM corp to get involved and they want to call the shots. If the dealer doesn't follow all their protocells nothing gets done. My car is now in a major tear down to repair the transmission. In my opinion GM should have sent a new transmission to make the repair. The repair didn't work and GM sent out a new transmission and corrected the problem. The car works great thanks to Keven Grover and his team.