GM Service Manual Online
For 1990-2009 cars only

    Object Number: 899636  Size: SH
  1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle .
  2. Remove the nuts securing the catalytic converter to the right exhaust manifold.
  3. Lower the vehicle.
  4. Remove the spark plugs. Refer to Spark Plug Replacement .

  5. Object Number: 899632  Size: SH
  6. Remove the heat shield bolts, and shield from the exhaust manifold.
  7. Remove the exhaust manifold bolts, manifold, and gasket.
  8. Discard the gasket.
  9. Clean and inspect the exhaust manifold. Refer to Exhaust Manifold Cleaning and Inspection .

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.

Important: Do not apply sealant to the first 3 threads of the bolt.

    Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 741554  Size: SH
  1. 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.
  2. Install the exhaust manifold NEW gasket and bolts.
  3. Tighten

    1. Tighten the bolts a first pass to 15 N·m (11 lb ft). Tighten the 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 25 N·m (18 lb ft). Tighten the bolts beginning with the center 2 bolts. Alternate from side-to-side, and work toward the outside bolts.
  4. Install the heat shield, and bolts to the exhaust manifold.
  5. Tighten
    Tighten the bolts to 9 N·m (80 lb in).

  6. Using a flat punch, bend over the exposed edge of the exhaust manifold gasket at the front of the right cylinder head.
  7. Install the spark plugs. Refer to Spark Plug Replacement .
  8. Raise the vehicle.

  9. Object Number: 899636  Size: SH
  10. Install the nuts that secure the catalytic converter to the left exhaust manifold.
  11. Tighten
    Tighten the nuts to 50 N·m (37 lb ft).

  12. Lower the vehicle.