Found a tomy F! Mobil 1 car today. It was missing one pickup shoe, and the pickup shoe that remained was different dimensionally then the replacement shoes I put in (runs fine now). The question I have is that the rear of the chassis, the portion around the rear axle, is encased in metal. I haven't seen this before, is this common? Why was it done? How do you remove the back axle?

Thanks
Rich

It's a factory installed axle retainer. Axle retainers are used to keep the rear axle in place during a hard crash. You can slide it off to remove the rear axle. For most home racing and with stock 0.063 axles you'll seldom need an axle retainer anyway. I have a number of SG+ chassis with those retainers on them. Real racers don't use the factory retainers either, they fabricate their own from straight pins or stiff wire.