Application Fits for C/K, G/P, 6.5L diesel. The J-29872 Injection Pump Adjustment Wrench is required to adjust timing on the injection pump on the 6.5L diesel. Function Used to adjust timing on the injection pump on 6.5L diesel engines. Superior Material Made of superior-quality steel with high precision laser cut construction, strong, corrosion resistant and durable in use. Nice Design The J-29872-A Wrench is a 1/2″ drive and has two locator pins that engage into the injection pump hub so it may be rotated for timing. Packing List 1 x Injection Pump Adjusting Wrench More Picture Details .