On certain GM V-6 engines, the oil pump drive is difficult to get at, making it a real hassle to remove it to repair O-ring leaks. This tool removes the oil pump drive from the engine without first having to remove the exhaust cross-over pipe or other components. For 1987-89 2.8L V-6 engines; 1990-94 3.1L V-6 engines; and 1994 and newer 3100 V-6 engines.