Inspect the rear main/flywheel seal for leakage when inspecting the flywheel. Replace as necessary. The flywheel should be inspected for ring gear damage, fluid contamination, warpage flatness and thickness variations, speed and reference sensor damage, and surface irregularities such as scoring, cracking, and signs of overheating. If the flywheel's clutch surface shows signs of deterioration or wear, it should be replaced. Symptoms of an improper flywheel clutch surface include clutch chatter during engagement and disengagement, poor shifting qualities, or grabbing. If the rear main/flywheel seal is leaking or the flywheel needs to be replaced, it should be replaced at this time. An oil-saturated clutch disk can cause clutch slippage, burning odors, and poor disengagement and engagement qualities. Dual mass flywheels, such as the one installed on E36 models, have a viscous coupling that can be checked with the
Pressure Plate installed or removed. To check the viscous coupling, place a protective cloth over the pressure plate and rotate it in a clockwise direction until the flywheel barely begins to move. Match mark the pressure plate and the outer body of the flywheel. Then, rotate the pressure plate in a counterclockwise direction until the flywheel barely begins to move and match mark it again. The pressure plate should be able to be moved between the two match marks without excessive force or looseness.