My 2012 Chevy Malibu LTZ 3.6L automatic w/60,000 miled has been making straining noises when changing gears. I couldn't check the fluid level or color bc it's inside. Took to transmission shop. Did test drive w/owner. Was told, without looking at it or taking it apart, that fluid top-off or drain and fill with new filter would not fix but need rebuild. Ugh! No burnt smell, no bucking when slowing/stopping, no light on dash, but definitely running rough. Left car w/him bc I didn't dare drive it more. There's no way for me to verify if he rebuilds it bc of the work involved in just getting to it. He's had it since yesterday. If I wanted to take it, he could say he's in the middle of fixing it already. Read some awful reviews after the fact. Was referred there by mechanic, but he doesn't know them. Help!