GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2001 🢒 Chevy C Cab/Chassis HD (GMT 400) 🢒 Engine 🢒 Engine Mechanical - 6.5L 🢒 Upper Intake Manifold Replacement

Removal Procedure

    Object Number: 358421 Size: SH
  1. Remove the upper intake manifold cover from the upper intake manifold.
  2. Disconnect both the battery negative cables from the batteries. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.

    3. Object Number: 177115 Size: SH
  3. Remove the braces from the turbocharger to the upper intake manifold.

    4. Object Number: 26957 Size: SH
  4. Remove the boost pressure sensor from the upper intake manifold.

    5. Object Number: 73425 Size: SH
  5. Remove the intake air temperature sensor from the upper intake manifold.

    6. Object Number: 520276 Size: SH

    Important: In order to loosen the sealer, run a small screw driver (flat blade) between the hose and the upper intake manifold. Use caution as not to damage the hose.

  6. Loosen the clamps on the hose between the turbocharger and the upper intake manifold.

    7. Object Number: 497281 Size: SH

    Important: When removing the upper intake manifold, rotate the upper intake manifold in a downward then in an upward motion to help loosen the silicone sealant on the air intake hose.

  7. Remove the upper intake manifold from the lower intake manifold.

    8. Object Number: 493966 Size: SH
  8. Remove the upper intake manifold gasket from the lower intake manifold gasket.

Installation Procedure

    Important: Install the air intake hose between the upper intake manifold and the turbocharger on the upper intake manifold first before installing the upper intake manifold.


    Object Number: 520276 Size: SH
  1. Apply a small amount of RTV sealant GM P/N 12346286 (Canadian P/N 10953472) to the hose between the turbocharger inlet and the upper intake manifold.

    2. Object Number: 493966 Size: SH
  2. Install the new upper intake manifold gasket.

    3. Object Number: 497281 Size: SH
  3. Install the upper intake manifold.

    4. 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.

  4. Install the mounting bolts in the upper intake manifold.

    5. Tighten
    Tighten the bolts to 23 N·m (17 lb ft).


    Object Number: 59746 Size: SH
  5. Tighten the air intake hose clamps on the upper intake manifold.

    6. Tighten
    Tighten the clamps to 6 N·m (50 lb in).

  6. Install the boost pressure sensor on the upper intake manifold. Refer to Boost Sensor Replacement in Engine Controls-6.5L-L65.
  7. Install the intake air temperature sensor to the upper intake manifold. Refer to Intake Air Temperature Sensor Replacement in Engine Controls-6.5L (L65).
  8. Install the braces from the turbocharger to the upper intake manifold. Refer to Turbocharger Replacement .

    9. Object Number: 358421 Size: SH
  9. Install the upper engine cover to the upper intake manifold.
  10. Connect both the battery negative cables to the batteries. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.