GM Service Manual Online
For 1990-2009 cars only
  1. Inspect the following for the excessive wear or damage:
  2. • The oil pump outer gear
    • The oil pump inner gear
    • The oil pump cover
    • The oil pump body

    Object Number: 236061  Size: SH
  3. Measure the radial clearance between the oil pump outer gear and the oil pump body using a feeler gage.
  4. Replace the oil pump outer gear and/or oil pump if the clearance exceeds 0.325 mm (0.01280 in).


    Object Number: 236054  Size: SH
  5. Measure the side clearance between the oil pump gears and a straightedge using a feeler gage.
  6. Replace the gears if the clearance exceeds 0.16 mm (0.0062 in).


    Object Number: 236057  Size: SH
  7. Measure the tip clearance between the oil pump gear tips using a feeler gage.
  8. Replace the gears if the clearance exceeds 0.35 mm (0.0138 in).