The OAP004 Overrunning Alternator Pulley has an outside diameter of 55.6mm and width of 36.5mm. The inside diameter of the mounting hole is 17mm and the pulley suits a 6PK belt. Please confirm dimensions match before ordering as some variation may exist based on year, engine code, and configuration.

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

Auxilliary systems such as power seats, heated and cooled seats, GPS navigation systems, electric power steering systems, on board entertainment systems and more all place increased strain on alternators, front end accessory drives and drive belts, unless managed effectively by quality overrunning alternator pulleys.

Dayco OAPs allow the alternator to ‘freewheel’ when the belt speed drops and are engineered with one-way clutches that allows 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.

Note: Overrunning alternator pulleys require special tools for removal and fitment.

Suitable for the following applications. Please confirm details before ordering:

• Holden|Captiva|Mar 2007 - Jan 2011|2.0L 4 cyl SOHC 16V DTFI Turbo Diesel CG|Eng code: Z20S1|OAP (Alt Bosch)
• Holden|Epica|Jul 2008 - Feb 2011|2.0L 4 cyl SOHC 16V DTFI Turbo Diesel EP|Eng code: Z20S1|OAP
• Mercedes Benz|MB 140|Nov 1999 - Jan 2005|2.9L 5 cyl DOHC 10V Di Diesel|Eng code: OM662.911|OAP
• Mercedes Benz|MB 100|1997 - 2005|2.9L 5 cyl SOHC 10V Diesel 661|Eng code: OM662.911|OAP
• Ssangyong|Korando|May 2004 - Jun 2007|2.9L 5 cyl SOHC 10V DTFI Turbo Diesel|Eng code: OM662.920|OAP
• Ssangyong|Musso|May 2004 - Sep 2007|2.9L 5 cyl SOHC 10V DTFI Turbo Diesel|Eng code: OM662 920|OAP