Based on the GM AD244 chassis. the tried-and-true G series of alternators are our best sellers. Reasonably priced and very durable. these units feature solid copper custom rectifiers for great durability. 6 oversize press fit diodes and premium bearings ensure long life even in hot or abusive conditions. This unit comes equipped with a smaller 1.75 inch diameter alternator pulley. and will require a slightly shorter drive belt for proper belt tension. This alternator integrates normally with the OEM GM engine computer and RVC load sensor. so charging voltage will still be controlled by the ECU. Upgraded positive and negative battery cables must be routed in a specific way on these vehicles in order for the system to function normally. please review the included instructions carefully. Not recommended for use above 5.500 RPM engine speed.