ACDelco GM Original Equipment Automatic Transmission Clutch Pack Piston is a GM-recommended replacement component for one or more of the following vehicle systems: automatic transmission/transaxle, and/or manual drivetrain and axles. This original equipment piston will provide the same performance, durability, and service life you expect from General Motors. AC Delco automatic transmission clutch pack piston’s built a reputation in the automotive industry for quality and craftmanship.