The big block Chevy engine uses a two-piece rear main seal through 1985. This means that half of the seal is on the rear main bearing cap and the other half is on the engine. Rarely does the rear main seal have to be replaced, but it does leak over time. Once it starts to leak,...
Another consideration is the condition of the car when you sign up. If your car has had a leaking seal for a while and your plan is to sign up, pay $90 for a few months and they have the engine pulled and rebuilt, forget it. These companies are savvy and have ways to prevent you...