Just a note, these cars came with two different rear ends. One had a differential and thus could turn much better. The solid axle version couldn't turn as smoothly. Pick the car up and spin one wheel. If the other wheel spins in the opposite direction, it has a differential. Now spin both tires listening/feeling for stripped gears in both the Fast and Slow gears. It's common for the Slow gear to strip, usually due to smacking reverse while going full speed forward or vise versa.
