I have a 2011 Chevy Cruze LT and recently had to have the transmission rebuilt. Apparently something within the trans broke off and caused mayhem, at least that’s how he put it in layman’s terms for me lol. I’ve had the car back for a few days and whenever I accelerate and I’m driving the car makes this soft (but noticeable above music) whining/rattling sound - like chains or gears? However when I’m idling or stopped the noise stops too. The mechanic said there’s going to be a break in period but he never mentioned anything about noises. So far the car is driving well, and it’s a little stiff but it’s driving better than it did before. Luckily I have a 2 year warranty (or 24,000 miles), but is this normal?