GM Service Manual Online
For 1990-2009 cars only

Removal Procedure


    Object Number: 1708617  Size: SH
  1. Remove the heated oxygen sensor (HO2S). Refer to Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 .
  2. Fully raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle .
  3. Remove the catalytic converter to exhaust manifold nuts. (1500 series shown, 2500 series similar).
  4. Remove the front wheel house liner - right side. Refer to Front Wheelhouse Liner Replacement - Right Side .

  5. Object Number: 1962351  Size: SH
  6. Partially lower the vehicle in order to work through the wheel opening.
  7. Remove the spark plug wires (1) from the spark plugs.
  8. 6.1. Twist the spark plug wire boot a 1/2 turn.
    6.2. Pull only on the boot in order to remove the wire from the spark plug.
  9. Remove the spark plug wires from the ignition coils.
  10. 7.1. Twist the spark plug wire boot a 1/2 turn.
    7.2. Pull only on the boot in order to remove the wire from the ignition coil.
  11. Remove the oil level indicator tube from the engine block. Refer to Oil Level Indicator and Tube Replacement .

  12. Object Number: 1708618  Size: SH
  13. Remove the exhaust manifold bolts and exhaust manifold.
  14. Remove and discard the exhaust manifold gasket.
  15. Remove and discard the exhaust manifold seal.

  16. Object Number: 1708619  Size: SH
  17. If replacing the exhaust manifold, remove the exhaust manifold heat shield bolts, and shield from the exhaust manifold.

Installation Procedure

Important: 

   • Tighten the exhaust manifold bolts as specified in the service procedure. Improperly installed and/or leaking exhaust manifold gaskets may affect vehicle emissions and/or On-Board Diagnostics (OBD) II system performance.
   • The cylinder head exhaust manifold bolt hole threads must be clean and free of debris or threadlocking material.
   • Do not apply sealant to the first 3 threads of the bolt.

    Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1708619  Size: SH
  1. If the exhaust manifold was replaced, position and install the exhaust manifold heat shield, and bolts to the exhaust manifold.
  2. Tighten
    Tighten the bolts to 9 N·m (80 lb in).


    Object Number: 1708618  Size: SH
  3. Clean the threads of the exhaust manifold bolts.
  4. Apply a 5 mm (0.2 in) wide band of threadlock GM P/N 12345493 (Canadian P/N 10953488), or equivalent to the threads of the exhaust manifold bolts.
  5. Install a NEW catalytic converter seal to the exhaust manifold.
  6. Position the NEW exhaust manifold gasket and exhaust manifold to the cylinder head.
  7. Ensure that the catalytic converter seal is seated to the catalytic converter.
  8. Install the exhaust manifold bolts.
  9. Tighten

    1. Tighten the bolts a first pass to 15 N·m (11 lb ft). Tighten the exhaust manifold bolts beginning with the center 2 bolts. Alternate from side-to-side, and work toward the outside bolts.
    2. Tighten the bolts a final pass to 20 N·m (15 lb ft). Tighten the exhaust manifold bolts beginning with the center 2 bolts. Alternate from side-to-side, and work toward the outside bolts.
  10. Using a flat punch, bend the gasket tab at the rear of the gasket around the cylinder head edge.
  11. Install the oil level indicator tube to the engine block. Refer to Oil Level Indicator and Tube Replacement .

  12. Object Number: 1962351  Size: SH
  13. Install the spark plug wires (1) to the spark plugs.
  14. Install the spark plug wires to the ignition coils.
  15. Inspect the spark plug wires for proper installation.
  16. 12.1. Push sideways on each boot in order to inspect the seating.
    12.2. Reinstall any loose boot.
  17. Fully raise and support the vehicle.

  18. Object Number: 1708617  Size: SH
  19. Install the catalytic converter to exhaust manifold nuts. (1500 series shown, 2500 series similar).
  20. Tighten
    Tighten the nuts to 50 N·m (37 lb ft).

  21. Partially lower the vehicle in order to work through the wheel opening.
  22. Install the front wheel house liner - right front. Refer to Front Wheelhouse Liner Replacement - Right Side .
  23. Install the HO2S. Refer to Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 .
  24. Inspect the exhaust system for leaks.