After engine removal, inspect the flex plate or flywheel for damage and wear. Flex plates are found on vehicles equipped with automatic transmissions. Flywheels are found on vehicles equipped with manual transmissions.
A flex plate will wear and crack around the bolt holes. It must be replaced when this happens, because small cracks turn into big cracks over time. Both have a starter ring gear attached. If the ring gear is damaged on a flex plate, the entire flex plate should be replaced.
If the ring gear on a flywheel is damaged, it can often be removed and replaced. If the flywheels surface area has light surface cracks or scoring, it can be resurfaced. Resurfacing a flywheel insures that it will have the proper flatness and smooth finish. The surface area must be smooth and not warped. Warpage reduces the contact area of the flywheel, allowing it to slip. This slipping causes excessive heat, hotspots, and glazing.
Whenever removing a flywheel from an engines crankshaft, mark its position to the crankshaft. Replace the flywheel in this same position during reassembly. This insures the balance of the flywheel to the engine. An unbalanced flywheel can cause excessive drivetrain vibration.