Posts Tagged: OAD

Replace an overrunning Alternator Decoupler Pulley

Overrunning Alternator Decoupler Pulley OAD What is an Alternator decoupler pulley (ADP)? Many late model vehicles are equipped with alternators fitted with an Overrunning Alternator Decoupler Pulley or simply, OAD. The OAD is one-way clutch and shock absorber. It’s job is to improve engine efficiency. Car makers started installing OAD pulleys with the 1999 models. Compare the diameter of the alternator pulley to the diameter of the harmonic balancer and you’ll see that the alternator pulley is generally 1/3 the diameter of the balancer. That means the alternator rotates 3 … Read More