GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2007 🢒 TopKick C-Series (Conventional) C4/C5 🢒 Engine 🢒 Engine Electrical 🢒 Water Outlet Tube Replacement

Water Outlet Tube Replacement 6.6L LLY

Removal Procedure
  1. Remove the air cleaner. Refer to Air Cleaner Replacement for the 6.6L (LLY) engine.
  2. Drain the cooling system. Refer to Cooling System Draining and Filling .

    3. Object Number: 674532 Size: SH
  3. Remove the radiator inlet hose from the water outlet tube.

    4. Object Number: 1371593 Size: SH
  4. Open the clip and remove the wiring harness branch from the bracket.

    5. Object Number: 1335388 Size: SH
  5. Remove the bolt and wiring harness bracket at the thermostat housing.

    6. Object Number: 1334916 Size: SH
  6. Remove the main engine electrical harness connector bolts.

    7. Object Number: 1334921 Size: SH
  7. Disconnect the barometric sensor electrical connector.

    8. Object Number: 1334926 Size: SH
  8. Disconnect the turbocharger vane position sensor electrical connector.

    9. Object Number: 1334948 Size: SH
  9. Remove the main electrical harness bracket bolts.
  10. Remove the main electrical harness bracket.

    11. Object Number: 1335386 Size: SH
  11. Disconnect the turbocharger coolant inlet hose from the turbocharger bypass valve.

    12. Object Number: 1335391 Size: SH
  12. Remove the water outlet bolts.

    13. Object Number: 1335393 Size: SH
  13. Remove the water outlet.
  14. Remove and discard the O-ring seal.

Installation Procedure

    Object Number: 1335393 Size: SH
  1. Install a NEW O-ring seal to the water outlet.
  2. Lubricate the O-ring seal with clean engine coolant.
  3. Install the water outlet.

    4. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1335391 Size: SH
  4. Install the water outlet bolts.

    5. Tighten
    Tighten the bolts to 21 N·m (15 lb ft).


    Object Number: 1335386 Size: SH
  5. Connect the turbocharger coolant inlet hose to the turbocharger bypass valve.

    6. Object Number: 1334948 Size: SH
  6. Install the main electrical harness bracket.
  7. Install the main electrical harness bracket bolts.

    8. Tighten
    Tighten the bolts to 21 N·m (15 lb ft).


    Object Number: 1334926 Size: SH
  8. Connect the turbocharger vane position sensor electrical connector.

    9. Object Number: 1334921 Size: SH
  9. Connect the barometric sensor electrical connector.

    10. Object Number: 1334916 Size: SH
  10. Install the main engine electrical harness connector bolts.

    11. Tighten
    Tighten the bolts to 10 N·m (89 lb in).


    Object Number: 1335388 Size: SH
  11. Install the wiring harness bracket and bolt to the thermostat housing.

    12. Tighten
    Tighten the bolt to 10 N·m (89 lb in).


    Object Number: 1371593 Size: SH
  12. Install the wiring harness branch to the bracket and close the clip.

    13. Object Number: 674532 Size: SH
  13. Install the radiator inlet hose to the water outlet tube.
  14. Install the air cleaner. Refer to Air Cleaner Replacement for the 6.6L (LLY) engine.
  15. Fill the cooling system. Refer to Cooling System Draining and Filling .

Water Outlet Tube Replacement 6.6L LMM

Removal Procedure

    Object Number: 1335388 Size: SH
  1. Drain the cooling system. Refer to Cooling System Draining and Filling .
  2. Remove the charge air cooler inlet pipe. Refer to Charge Air Cooler Inlet Pipe Replacement .
  3. Remove the radiator inlet hose. Refer to Radiator Inlet Hose Replacement .
  4. Remove the turbocharger coolant bypass valve. Refer to Turbocharger Coolant Bypass Valve Replacement .
  5. Remove the bolt and wiring harness bracket at the thermostat housing.

    6. Object Number: 1334916 Size: SH
  6. Remove the main engine electrical harness connector bracket bolts.

    7. Object Number: 1731857 Size: SH
  7. Disconnect the turbocharger vane position sensor electrical connector.

    8. Object Number: 1869687 Size: SH
  8. Remove the main electrical harness bracket bolts.
  9. Remove the main electrical harness bracket.

    10. Object Number: 1869796 Size: SH
  10. Remove the water outlet bolts.
  11. Remove the Idle Air Temperature sensor from the pipe.

    12. Object Number: 1335393 Size: SH
  12. Remove the water outlet.
  13. Remove and discard the O-ring seal.

Installation Procedure

    Object Number: 1335393 Size: SH
  1. Install a NEW O-ring seal to the water outlet.
  2. Lubricate the O-ring seal with clean engine coolant.
  3. Install the water outlet.

    4. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1869796 Size: SH
  4. Install the water outlet bolts.

    5. Tighten
    Tighten the bolts to 21 N·m (15 lb ft).


    Object Number: 1869687 Size: SH
  5. Install the main electrical harness bracket.
  6. Install the main electrical harness bracket bolts.

    7. Tighten
    Tighten the bolts to 21 N·m (15 lb ft).


    Object Number: 1731857 Size: SH
  7. Connect the turbocharger vane position sensor electrical connector.

    8. Object Number: 1334916 Size: SH
  8. Install the main engine electrical harness connector bracket bolts.

    9. Tighten
    Tighten the bolts to 10 N·m (89 lb in).


    Object Number: 1335388 Size: SH
  9. Install the wiring harness bracket and bolt to the thermostat housing.

    10. Tighten
    Tighten the bolt to 10 N·m (89 lb in).

  10. Install the turbocharger coolant bypass valve. Refer to Turbocharger Coolant Bypass Valve Replacement .
  11. Install the radiator inlet hose. Refer to Radiator Inlet Hose Replacement .
  12. Install the charge air cooler inlet pipe. Refer to Charge Air Cooler Inlet Pipe Replacement .
  13. Fill the cooling system. Refer to Cooling System Draining and Filling .