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For 1990-2009 cars only

Turbocharger Coolant Bypass Valve Replacement 6.6L (LB7) Engine

Removal Procedure


    Object Number: 813243  Size: SH
  1. Loosen the outlet duct clamp at the upper intake manifold cover.
  2. Remove the upper intake manifold cover from the outlet duct.
  3. Remove the upper intake manifold cover.
  4. Drain the cooling system. Refer to Cooling System Draining and Filling .

  5. Object Number: 668427  Size: SH
  6. Disconnect the turbocharger coolant return hose from the turbocharger bypass valve.

  7. Object Number: 687052  Size: SH
  8. Remove the turbocharger bypass valve and washer.

Installation Procedure


    Object Number: 687052  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 turbocharger bypass valve and washer.
  2. Tighten
    Tighten the valve to 60 N·m (44 lb ft).


    Object Number: 668427  Size: SH
  3. Connect the turbocharger coolant return hose to the turbocharger bypass valve.

  4. Object Number: 813243  Size: SH
  5. Install the upper intake manifold sight shield.
  6. Install the upper intake manifold cover to the outlet duct.
  7. Tighten the outlet duct clamp at the upper intake manifold cover.
  8. Tighten
    Tighten the clamp to 6 N·m (53 lb in).

  9. Fill the cooling system. Refer to Cooling System Draining and Filling .

Turbocharger Coolant Bypass Valve Replacement 6.6L (LLY) Engine

Removal Procedure


    Object Number: 1335386  Size: SH
  1. Remove the intake manifold cover. Refer to Intake Manifold Cover Replacement in Engine Mechanical - 6.6L (LLY).
  2. Drain the cooling system. Refer to Cooling System Draining and Filling .
  3. Reposition the coolant inlet hose clamp.
  4. Disconnect the turbocharger coolant inlet hose from the turbocharger bypass valve.

  5. Object Number: 687052  Size: SH
  6. Remove the turbocharger bypass valve and washer.

Installation Procedure

    Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 687052  Size: SH
  1. Install the turbocharger bypass valve and washer.
  2. Tighten
    Tighten the valve to 60 N·m (44 lb ft).


    Object Number: 1335386  Size: SH
  3. Connect the turbocharger coolant inlet hose to the turbocharger bypass valve.
  4. Position the coolant inlet hose clamp.
  5. Fill the cooling system. Refer to Cooling System Draining and Filling .
  6. Install the intake manifold cover. Refer to Intake Manifold Cover Replacement in Engine Mechanical - 6.6L (LLY).