'If you mesh the gears correctly You shouldn't have any problems with them. I keep a spare set handy just in case but because of the proper gearing they collect dust... The last time I needed to replace them was jumpimg my mt2 at a skate board park on Marthas Vinyard this summer. I was jumping about 8-10 feet and the motor worked its way loose, Other than that, never had any problems. Love the truck and very few problems