GM Service Manual Online
For 1990-2009 cars only

Special Tools

    • J 35268-A Camshaft/Front Main Seal Installer
    • J 36660-A Torque/Angle Meter
    • J 42098 Crank Hub TORX Socket
    • J 42065 Crank Hub Holding Tool

Removal Procedure

  1. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection.
  2. Recover the A/C system. Refer to Refrigerant Recovery and Recharging.
  3. Drain the coolant. Refer to Cooling System Draining and Filling.
  4. Drain the engine oil. Refer to Engine Oil and Oil Filter Replacement.
  5. Remove the intake air resonator. Refer to Intake Air Resonator Replacement.
  6. Remove the intake plenum. Refer to Intake Plenum Replacement.
  7. Remove the timing belt. Refer to Timing Belt Replacement.
  8. Remove the rear timing belt cover. Refer to Timing Belt Rear Cover Replacement.
  9. Remove the A/C compressor. Refer to Air Conditioning Compressor Replacement.
  10. Remove the A/C compressor and power steering pump bracket bolts from the engine block.
  11. Position the A/C-PS bracket out of the way of the oil pump housing and secure with mechanic's wire.

  12. Object Number: 158549  Size: SH
  13. Remove the generator lower mounting bolt (3).
  14. Loosen the upper generator mounting bolt (6).
  15. Pivot the generator out of the way and secure with mechanic's wire.
  16. Remove the lower oil pan. Refer to Lower Oil Pan Replacement.
  17. Remove the upper oil pan. Refer to Upper Oil Pan Replacement.

  18. Object Number: 217371  Size: SH
  19. Mount the J 42065 to the crankshaft drive gear.
  20. Use the J 42098 to remove the crankshaft drive gear bolt.

  21. Object Number: 159205  Size: SH
  22. Remove the crankshaft drive gear.

  23. Object Number: 345859  Size: SH
  24. Remove the oil pump bolts.
  25. Discard the old oil pump bolts.
  26. Remove the oil pump.
  27. Remove the front main oil seal and collar from the oil pump.

  28. Object Number: 159481  Size: SH
  29. Clean the oil pump sealing surfaces if the pump is to be reinstalled.
  30. Clean the engine block (1) and the upper oil pan sealing surfaces.
  31. Ensure all of the old sealant, gasket material and residual oil is removed.
  32. Ensure the guide pins (2) are in place.

Installation Procedure


    Object Number: 345868  Size: SH

    Important: Do not cover and/or restrict the gasket openings and oil passages with sealant. Only apply sealant to the crosshatched area of the gasket as shown in the illustration.

  1. Coat only the pump side of the new oil pump gasket with a thin, even coating of GM P/N 1052942 or equivalent.
  2. Install the oil pump gasket.

  3. Object Number: 159481  Size: SH
  4. Install the oil pump and align with the guide pins (2).
  5. Coat the new oil pump bolts with GM P/N 12345493 or equivalent.
  6. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 345868  Size: SH
  7. Install the oil pump bolts. Tighten in the sequence shown.
  8. Tighten
    Tighten the oil pump bolts to 12 N·m (9 lb ft).


    Object Number: 159205  Size: SH
  9. Install the collar.
  10. Coat the lip of the front main oil seal with a small amount of GM P/N 12377985 chassis grease, or equivalent, to aid in installation.
  11. Install the front main oil seal.
  12. Use the J 35268-A to tap the front main oil seal into place.
  13. Ensure the front main oil seal if fully and evenly seated.

  14. Install the crankshaft drive gear.
  15. Install a new crankshaft drive gear bolt.
  16. Tighten
    Tighten the crankshaft drive gear bolt, while counterholding with J 42065 , to 250 N·m (184 lb ft) on the first pass, 45 degrees on the second pass and 15 degrees on the third pass.

  17. Install the upper oil pan. Refer to Lower Oil Pan Replacement.
  18. Install the lower oil pan. Refer to Upper Oil Pan Replacement.

  19. Object Number: 158549  Size: SH
  20. Release and pivot the generator into place and install the generator lower mounting bolt (3).
  21. Tighten

        • Tighten the generator lower mounting bolt to 35 N·m (26 lb ft).
        • Tighten the generator upper mounting bolt to 40 N·m (30 lb ft).

    Important: The oil pump bolts must be re-tightened AFTER the generator mounting bolt has been tightened to specifications to allow for uniform compression of the oil pump gasket.

  22. Re-tighten the oil pump bolts. Tighten in the sequence shown.
  23. Tighten
    Tighten the oil pump bolts to 20 N·m (15 lb ft).

  24. Re-position the A/C compressor and power steering pump bracket.
  25. Install the A/C compressor and power steering pump bracket bolts.
  26. Tighten
    Tighten the A/C compressor and power steering pump bracket bolts to 40 N·m (30 lb ft).

  27. Install the A/C compressor. Refer to Air Conditioning Compressor Replacement.
  28. Install the rear timing belt cover. Refer to Timing Belt Rear Cover Replacement.
  29. Install the timing belt. Refer to Timing Belt Replacement.
  30. Install the intake plenum. Refer to Intake Plenum Replacement.
  31. Install the intake air resonator. Refer to Intake Air Resonator Replacement.
  32. Charge the A/C system. Refer to Refrigerant Recovery and Recharging.
  33. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection.
  34. Fill the crankcase with engine oil. Refer to Engine Oil and Oil Filter Replacement.
  35. Fill the cooling system. Refer to Cooling System Draining and Filling.