I own a 2017 Canyon with a 2.8L diesel. I had a problem with the gears shifting hard and brought it in for servicing at 47,000 mi (just before the expiration of the powertrain warranty). The dealer replaced "TEHCM" and "set the fluid level" whatever that means. It was okay for several months, but the problem returned. I brought the truck in again with the same complaint, this time at 62,000 mi and beyond the warranty period. Now GMC says it needs a new transmission and GMC will not cover the replacement under warranty. For obvious reasons, this doesn't sit well with me. I wonder what my legal options are. BTW, I'm an older guy that drives very conservatively. Can't imagine anything about my driving that would have caused a transmission failure.