Litens Automotive is the original equipment supplier to GM for this decoupling alternator pulley. This replacement pulley is also designed and produced by Litens and is exact in all form, fit, and performance characteristics as the original equipment part (with the exception of not having the car manufacturer's logo or part number applied to the part). Decoupling pulleys are engine specific and should never be interchanged with other types of pulley technology. The Litens OAD type pulley is designed to free-wheel in one direction and, with an internal spring and damping device, softly engage in the opposite direction. The OAD is designed as a sacrificial part of the front-end accessory drive system, protecting other belt driven component as well as the alternator. The correct decoupler pulley ensures smooth, quiet performance as well as increasing vehicle gas mileage. Under normal driving conditions, the original pulley will require replacement in approx. 35,000 - 50,000 miles. Fits Chevy Impala Police Vehicles 3.9L with cylinder deactivation. Product Features:
- Patented Original Equipment Design.
- Protects the alternator and other front-end accessory drive components.
- Installation instructions included.
- New plastic cap included with the OAD.
- Tools Required - Litens recommends using Miller Special Tools P/N 8433A and a torque wrench.
- Professional mechanics can install this replacement OAD in approximately 1 hour. During alternator replacement, belts, tensioners, and routing pulleys should be inspected.