Feaute APPLICATION: Replaces to J-29872-A, works on C/K, G/P, 6.5L diesel. FUNCTION: Used to adjust timing on the injection pump on 6.5L diesel engines. DESIGN:The J-29872-A is 1/2″ square drive and has two locator pins that engage into the injection pump hub to timing adjustment. CONSTRUCTION: Made of superior-quality steel with high precision laser cut construction for carefree use and perfect match. .