GM Service Manual Online
For 1990-2009 cars only

Heater Outlet Hose Replacement Utility LR4, LM7, LQ4

Removal Procedure

  1. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  2. Remove the air intake tube.
  3. Remove the heater and surge tank hoses from the mounting clip.

  4. Object Number: 12777  Size: SH
  5. Squeeze the plastic retainer release tabs.

  6. Object Number: 12778  Size: SH
  7. Pull the connection apart.

  8. Object Number: 363237  Size: SH
  9. Remove the outlet heater hose from the water pump.
  10. Reposition the outlet heater hose clamp at the surge tank.
  11. Remove the outlet heater hose from the surge tank.

  12. Object Number: 363118  Size: SH
  13. Remove the outlet heater hose.

Installation Procedure


    Object Number: 363118  Size: SH
  1. Install the outlet heater hose.

  2. Object Number: 363237  Size: SH
  3. Install the outlet heater hose to the water pump.
  4. Install the outlet heater hose to the surge tank.
  5. Install the outlet heater hose clamp to the surge tank.

  6. Object Number: 21855  Size: SH
  7. Connect the heater and surge tank hoses to the heater core.
  8. Important: Firmly push the quick connect onto the heater core hose until you hear an audible click.

  9. Pull the heater outlet hose to ensure the connection.
  10. Install the heater and surge tank hoses to the mounting clip.
  11. Install the air intake tube.
  12. Fill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.

Heater Outlet Hose Replacement Avalanche/Xlt LR4, LM7, LQ4

Tools Required

J 43181 Quick Connect Connector Removal Tool

Removal Procedure

  1. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  2. Remove the air intake tube.
  3. Remove the heater and surge tank hose from the mounting clip.

  4. Object Number: 362171  Size: SH
  5. Using the J 43181 disconnect the heater hose from the heater core outlet.
  6. 4.1. Install the J 43181 to the heater core pipe.
    4.2. Close the tool around the heater core pipe.
    4.3. Firmly pull the tool into the quick connect end of the heater hose.
    4.4. Firmly grasp the heater hose. Pull the heater hose forward in order to disengage the hose from the heater core.

    Object Number: 363237  Size: SH
  7. Remove the outlet heater hose from the engine.

  8. Object Number: 363118  Size: SH
  9. Remove the outlet heater hose.

Installation Procedure


    Object Number: 363118  Size: SH
  1. Install the outlet heater hose.

  2. Object Number: 363237  Size: SH
  3. Install the outlet heater hose to the engine.
  4. Connect the outlet heater hose to the heater core.
  5. Firmly push the quick connect onto the heater core pipe until you hear an audible click.

  6. Install the heater and surge tank hose to the mounting clip.
  7. Install the air intake tube.
  8. Fill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.

Heater Outlet Hose Replacement Utility 8.1L

Removal Procedure

  1. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  2. Remove the heater and surge tank hoses from the mounting clip.

  3. Object Number: 12777  Size: SH
  4. Squeeze the plastic retainer release tabs.

  5. Object Number: 12778  Size: SH
  6. Pull the connection apart.

  7. Object Number: 659059  Size: SH
  8. Reposition the surge tank outlet hose clamp at the surge tank.
  9. Remove the surge tank outlet hose (2) from the surge tank.

  10. Object Number: 1275812  Size: SH
  11. Remove the radiator outlet hose from the radiator. Refer to Radiator Hose Quick Connect Fitting .

  12. Object Number: 751427  Size: SH
  13. Reposition the outlet hose clamp the water pump.
  14. Remove the outlet hose from the water pump.

Installation Procedure


    Object Number: 751427  Size: SH
  1. Install the outlet hose to the water pump.
  2. Position the outlet hose clamp to the water pump.

  3. Object Number: 659059  Size: SH
  4. Install the surge tank outlet hose (2) from the surge tank.
  5. Position the surge tank outlet hose clamp to the surge tank.

  6. Object Number: 1275812  Size: SH
  7. Install the radiator outlet hose to the radiator. Refer to Radiator Hose Quick Connect Fitting .

  8. Object Number: 21855  Size: SH
  9. Connect the heater and surge tank hoses to the heater core.
  10. Important: Firmly push the quick connect onto the heater core pipe until you hear an audible click.

  11. Pull the heater outlet hose to ensure the connection.
  12. Install the heater and surge tank hoses to the mounting clip.
  13. Fill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.

Heater Outlet Hose Replacement Avalanche/Xlt 8.1L

Tools Required

J 43181 Quick Connect Connector Removal Tool

Removal Procedure


    Object Number: 1275812  Size: SH
  1. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  2. Remove the radiator outlet hose from the radiator. Refer to Radiator Hose Quick Connect Fitting .

  3. Object Number: 362171  Size: SH
  4. Using the J 43181 disconnect the heater hoses from the heater core outlet.
  5. 3.1. Install the J 43181 to the heater core pipe.
    3.2. Close the tool around the heater core pipe.
    3.3. Firmly pull the tool into the quick connect end of the heater hose.
    3.4. Firmly grasp the heater hose. Pull the heater hose forward in order to disengage the hose from the heater core.

    Object Number: 659059  Size: SH
  6. Reposition the surge tank outlet hose clamp at the surge tank.
  7. Remove the surge tank outlet hose (2) from the surge tank.

  8. Object Number: 751427  Size: SH
  9. Reposition the outlet hose clamp the water pump.
  10. Remove the outlet hose from the water pump.

Installation Procedure


    Object Number: 751427  Size: SH
  1. Install the outlet hose to the water pump.
  2. Position the outlet hose clamp to the water pump.

  3. Object Number: 659059  Size: SH
  4. Install the surge tank outlet hose (2) from the surge tank.
  5. Position the surge tank outlet hose clamp to the surge tank.

  6. Object Number: 362171  Size: SH
  7. Connect the heater and surge tank hoses to the heater core.
  8. Firmly push the quick connect onto the heater core pipe until you hear an audible click.


    Object Number: 1275812  Size: SH
  9. Install the radiator outlet hose to the radiator. Refer to Radiator Hose Quick Connect Fitting .
  10. Fill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.