With the ever increasing number of accessories and auxiliary systems that require extra electrical power in modern cars, Overrunning Alternator Pulleys (OAPS) are becoming increasingly popular on many late model vehicles to deal with increased alternator loads and engine torsional fluctuations.

Dayco OAPs allow the alternator to “freewheel” when the belt speed drops and are engineered with one-way clutches that allow the rotational inertia of the alternator to “overrun” during any belt deceleration. Dayco OAPs, which are designed for long service life, decrease drive belt vibration and reduce belt slippage during rapid acceleration or deceleration, resulting in reduced stress on the drive belt and other accessories as well as increased alternator and drive belt life.