Had my transmission replaced (6-speed manual) last winter when my car was around 60K miles. It was whining like a bad wheel bearing does. Service manager told me it was the bearing and that GM didn't have a replacement part, so they'd just be giving me a new transmission. Gave me a 2014 Volt with less than 1500 miles on it for a loaner and got to test drive that for four days.

I'm up to 85K now and this transmission seems to be holding up well. However, I still get the grind sometimes when I shift hard, which I was hoping to be eliminated by the replacement.
Thank goodness for the 100,000 mile warranty or else I would have been in trouble financially.