GM Service Manual Online
For 1990-2009 cars only

    Object Number: 71393  Size: SH
  1. Remove the drive spacer (7) from the oil pump housing.
  2. Remove the two screws (8) holding the pump housing halves (6, 1) together.
  3. Remove the inner (drive) and the outer (driven) rotors (5) from the housing. Note the orientation of the pump rotors. The outer rotor has one chamfered edge. The chamfered edge must be face-down (closest to the rear of the engine) in the pump body (1).
  4. Remove the oil pressure relief valve (2) as follows:
  5. 4.1. Remove the pressure relief valve cap retaining pin (4).
    4.2. Remove the retaining plug without damaging the O-ring seal.
    4.3. Slide the pressure relief valve spring and piston out of its bore.