Hey everyone! I was driving my volcano today and it was running fine and then for some reason I felt like the rear wheels weren't spinning, and it seemed like only the front wheels were spinning. The shaft that connects to the disc brake was not moving. Is it a gear that may be stripped? i heard of gears going bad real easy on these cars? could it be the gear? If the disc brake is loose will that make the shaft not spin? I checked and made sure that the grub screw was in the rear drive shaft. Any ideas? Thanks!