Ok, I have a RTR caster fusion that came with a hobbywing 80A ESC and a FUSION 2000 motor. I put the motor/esc in my converted Mugen MBX5T truggy and ran it a few races. Yesterday it sounded like my center diff went out and it had no power under load. Turns out as I give it gas you can hear the motor turn and it sounds dirty or broken and I can hold the truggy and the pinion doesn't move. It doesn't slip at the shaft. Is this how they go, or do I need to clean the motor somehow?