ACDelco 12635649 GM Original Equipment Crankshaft Balancer Kit with Washers Reduces torsional vibration and serves as a pulley for the engine drive belts Designs are enhanced and amended to incorporate updates, upgrades, and Technical Service Bulletins GM-recommended replacement part for your GM vehicle's original factory component Offering the quality, reliability, and durability of GM OE Manufactured to GM OE specification for fit, form, and function