GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

  1. Remove the turbocharger assembly. Refer to Turbocharger Replacement .
  2. Remove the fuel junction block. Refer to Fuel Junction Block Replacement in Engine Controls - 6.6L.
  3. Remove the right fuel rail assembly. Refer to Fuel Injection Fuel Rail Assembly Replacement - Bank 1 in Engine Controls - 6.6L.
  4. Remove the intake manifold tube. Refer to Intake Manifold Tube Replacement

  5. Object Number: 657870  Size: SH
  6. Remove the 9 bolts and the 2 nuts from the intake manifold.
  7. A bolt is located in the intake manifold opening.

    Important: The intake manifold uses sealer. Pry at the area by the common rail bolt holes. Avoid damage to the sealing surfaces.

  8. Remove the intake manifold from the cylinder head.
  9. To prevent entry of debris in the cylinder head tape the openings.

Inspection and Repair

  1. Clean the sealant from the intake manifold and the cylinder head sealing surface.
  2. Clean the intake manifold in cleaning solvent and air dry.
  3. Inspect the intake manifold for cracking, distortion, and any damage.
  4. Replace the intake manifold if any of the above conditions exist.

Installation Procedure


    Object Number: 657871  Size: SH
  1. Apply a 2-3 mm (1/8 in) wide to 0.5-1.5 mm (1/16 in) high bead of sealer GM P/N 12378521 or equivalent to the sealing surface of the intake manifold.

  2. Object Number: 657870  Size: SH

    Important:  The left side and the right side intake manifolds are not interchangeable.

  3. Install the intake manifold to the cylinder head.

  4. Object Number: 654532  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.

  5. Install the intake manifold nine bolts and 2 nuts.
  6. Tighten
    Tighten the intake manifold bolts and nuts to 21 N·m (15 lb ft) in the sequence shown.

  7. Install the intake manifold tube. Refer to Intake Manifold Tube Replacement .
  8. Install the right fuel rail assembly. Refer to Fuel Injection Fuel Rail Assembly Replacement - Bank 2 in Engine Controls - 6.6L.
  9. Install the fuel junction block. Refer to Fuel Junction Block Replacement in Engine Controls - 6.6L.
  10. Install the turbocharger assembly. Refer to Turbocharger Replacement .