GM Service Manual Online
For 1990-2009 cars only

Exhaust Manifold Replacement - Left Side LH8

Removal Procedure

  1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle.
  2. Remove the left front tire and wheel assembly. Tire and Wheel Removal and Installation.
  3. Remove the left catalytic converter. Refer to Catalytic Converter Replacement - Left Side.
  4. Remove the upper intake manifold sight shield. Refer to Upper Intake Manifold Sight Shield Replacement
  5. Remove the spark plugs. Refer to Spark Plug Replacement.
  6. Remove the exhaust manifold heat shield. Refer to Exhaust Manifold Heat Shield Replacement - Left Side.

  7. Object Number: 1902499  Size: SH
  8. Working through the wheel well opening, remove the exhaust manifold bolts (1).
  9. Note: The Manifold is removed from below the vehicle.

  10. Remove the exhaust manifold (2) and gasket (3). Discard the gasket.

Installation Procedure

Note: 

   • 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.


    Object Number: 1902499  Size: SH

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

  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 one exhaust manifold bolt to the exhaust manifold (2) and place the NEW gasket (3) onto the bolt.
  3. Caution: Refer to Fastener Caution in the Preface section.

  4. Working through the wheel well opening, install the remaining exhaust manifold bolts (1).
  5. 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.
  6. Using a flat punch, bend over the exposed edge of the exhaust manifold gasket at the rear of the left cylinder head.
  7. Install the exhaust manifold heat shield. Refer to Exhaust Manifold Heat Shield Replacement - Left Side.
  8. Install the spark plugs. Refer to Spark Plug Replacement.
  9. Install upper intake manifold sight shield. Refer to Upper Intake Manifold Sight Shield Replacement
  10. Install the catalytic converter. Refer to Catalytic Converter Replacement - Left Side.
  11. Tighten
    Tighten the nuts to 50 N·m (37 lb ft).

  12. Install the left front tire and wheel assembly. Tire and Wheel Removal and Installation.
  13. Lower the vehicle.