GM Service Manual Online
For 1990-2009 cars only

    Warning: Refer to Safety Glasses Warning in the Preface section.


    Object Number: 186750  Size: SH
  1. Clean the oil pump components in cleaning solvent.
  2. Dry the components with compressed air.
  3. Inspect the oil pump for the following conditions:
  4. • Scoring on the top of the gears (1)
    • Damaged gears (2) for the following:
       - Chipping
       - Galling
       - Wear
    • Scoring, damage or casting imperfections to the body (3)
    • Damaged or scored gear shaft (4)
    • Damaged or scored gear shaft (5)
    • Damaged bolt hole threads
    • Worn oil pump driveshaft bore
    • Damaged or sticking oil pump pressure relief valve
      Minor imperfections may be removed with a fine oil stone.
    • Collapsed or broken oil pump pressure relief valve spring
  5. If the oil pump is to be reused, install a NEW oil pump pressure relief valve spring.
  6. During oil pump installation, install a NEW oil pump driveshaft retainer.