GM Service Manual Online
For 1990-2009 cars only

Important: The power steering pump pulley, the power steering pump shaft, and the power steering pump seals can be serviced. If any other internal parts of the power steering pump are found to be defective, replace the power steering pump.

    Notice: Use caution not to overtighten the vise. The power steering pump housing can distort if excessive pressure is exerted on its exterior.

  1. Mount the power steering pump assembly in a soft jaw vise.

  2. Object Number: 355301  Size: SH
  3. Remove the following components from the pump body:
  4. • The 2 bolts
    • The inlet pipe (2)
    • The O-ring
  5. Remove the pressure sensor (1) from the pump body (4).
  6. Remove the following components from the pump body (4):
  7. • The high pressure line connector (13)
    • The O-rings
    • The relief valve (12)
    • The spring (11)
  8. Remove the following components from the pump body (4):
  9. • The 4 bolts
    • The pump cover (7)
    • The O-ring
  10. Remove the cam ring (8) from the pump body (4).
  11. Remove the rotor vane plates from the rotor (9).
  12. Remove the snap ring from the pump shaft.
  13. Remove the rotor (9) from the pump body (4).
  14. Remove the pulley and the pump shaft (15) from the pump body (4).
  15. Remove the side plate (10) and the O-rings from the pump body (4).
  16. Use a flat-bladed tool in order to remove the pump shaft oil seal (14) from the pump body (4).
  17. Clean all of the power steering pump components.
  18. Dry the components thoroughly.


    Object Number: 355303  Size: SH
  19. Inspect the following items for excessive abrasion or damage. If you find any damage, replace the pump assembly. Refer to Power Steering Pump Replacement .
  20. • The pump body
    • The cover
    • The side plate
    • The shaft

    Object Number: 349460  Size: SH
  21. Inspect the cam ring for excessive abrasion and damage.
  22. If you find any damage, replace the pump assembly. Refer to Power Steering Pump Replacement .


    Object Number: 355305  Size: SH
  23. Inspect the rotor and vanes for excessive abrasion or damage. If you find any damage, replace the pump assembly. Refer to Power Steering Pump Replacement .

  24. Object Number: 355307  Size: SH
  25. Inspect the relief valve fluid passage for obstructions. Inspect the sliding surfaces for excessive abrasion and damage. If you find any damage, replace the pump assembly. Refer to Power Steering Pump Replacement .

  26. Object Number: 355312  Size: SH
  27. Measure the rotor and the vane plate clearance using a feeler gauge (1).
  28. The maximum rotor vane plate clearance is 0.06 mm (0.0023 in). If the rotor vane is greater than the specified value, replace the pump assembly. Refer to Power Steering Pump Replacement .


    Object Number: 355314  Size: SH
  29. Measure the free length of the relief spring (1) using the dial calipers.
  30. The free length of the spring should fall within 33.5 mm-36.5 mm (1.43-1.32 in). If the valve spring does not fall within the specification, replace the pump assembly. Refer to Power Steering Pump Replacement .