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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1998 🢒 Chevy P12 Chassis 🢒 Engine 🢒 Engine Mechanical - 7.4L 🢒 Exhaust Manifold Installation

Exhaust Manifold Installation Right


    Object Number: 180921 Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  1. Install the exhaust manifold studs, if removed.

    2. Tighten
    Tighten the exhaust manifold studs to 30 N·m (22 lb ft).

    Important: Make sure the 7.4 marking on the gasket is facing away from the cylinder head.

  2. Install the exhaust manifold gasket.
  3. Install the exhaust manifold.
  4. Install exhaust manifold nuts and center bolt.

    5. Tighten

    1. Tighten the exhaust manifold nuts to 30 N·m (22 lb ft).
    2. Tighten the exhaust manifold bolt to 54 N·m (40 lb ft).

    Object Number: 279541 Size: SH
  5. Install the spark plug heat shields.
  6. Install the spark plug heat shield nuts.

    7. Tighten
    Tighten the spark plug heat shield nuts to 20 N·m (15 lb ft).

  7. Install the spark plug wire boots onto the spark plugs.

Exhaust Manifold Installation Left


    Object Number: 276377 Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  1. Install the exhaust manifold studs, if removed.

    2. Tighten
    Tighten the exhaust manifold studs to 30 N·m (22 lb ft).

    Important: Make sure the 7.4 marking on the gasket is facing away from the cylinder head.

  2. Install the exhaust manifold gasket.
  3. Install the exhaust manifold.
  4. Install exhaust manifold nuts and center bolt.

    5. Tighten

    1. Tighten the exhaust manifold nuts to 30 N·m (22 lb ft).
    2. Tighten the exhaust manifold bolt to 54 N·m (40 lb ft).

    Object Number: 279541 Size: SH
  5. Install the spark plug heat shields.
  6. Install the spark plug heat shield nuts.

    7. Tighten
    Tighten the spark plug heat shield nuts to 20 N·m (15 lb ft).

  7. Install the spark plug wire boots onto the spark plugs.

    8. Object Number: 351814 Size: SH
  8. Install the exhaust manifold adapter, if removed.

    9. Tighten
    Tighten the exhaust manifold adapter to 160 N·m (118 lb ft).


    Object Number: 353999 Size: SH
  9. Install the exhaust gas recirculation valve (EGR) valve inlet pipe to the intake and exhaust manifolds.

    10. Tighten

        • Tighten the EGR inlet pipe nut at the intake manifold to 60 N·m (44 lb ft).
        • Tighten the EGR inlet pipe nut at the exhaust manifold to 60 N·m (44 lb ft).
  10. Install the EGR inlet pipe bracket bolt to the rear of the left cylinder head.

    11. Tighten
    Tighten the EGR inlet pipe bracket bolt to 50 N·m (37 lb ft).