2005 CADILLAC CTS User Comment / Complaint

My 2005 cadillac cts-v has been sent to the cadillac dealership numerous times concerning rear differential noise and clunking. after cadillac claimed that the problem was fixed by replacing the drive shaft, on the same night the rear differential blew up under normal driving condition. the car was sent back to cadillac and was denied warranty under the accusation of harsh driving or "hot rodding". there was no in-depth inspection or a mechanical and material analysis to determine the actual point of failure. the tech representative simple conducted a bias conclusion and accused me of "hot rodding".