GM Genuine Parts Engine Water Pump Cover Gaskets are designed, engineered, and tested to rigorous standards, and are backed by General Motors. These gaskets are used to seal the stamped metal plate on the backside of some GM water pumps. The water pump cover gasket can be made from fiber or a rubberized composite material that provides a liquid-tight connection. GM Genuine Parts are the true OE parts installed during the production of or validated by General Motors for GM vehicles. Some GM Genuine Parts may have formerly appeared as ACDelco GM Original Equipment (OE).