6.5L Diesel Injection Pump Adjusting Wrench for Diesel Engines 6.2L 6.5L (1/2″ Drive), Similar to J-29872-A, J-29872. Fits for C/K, G/P, 6.5L diesel. 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.