GM Service Manual Online
For 1990-2009 cars only

Heater Outlet Hose Replacement 4.3L, 4.8L, 5.3L, 6.0L

Tools Required

J 38185 Hose Clamp Pliers

Removal Procedure

  1. Partially drain the engine coolant. Refer to Cooling System Draining and Filling .
  2. Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement for the 4.3L engine or to Air Cleaner Assembly Replacement for the 4.8, 5.3, and 6.0L engine.
  3. Remove the heater hose clamps using the J 38185 .
  4. Remove the outlet heater hose from the outlet radiator hose connection.
  5. Remove the outlet heater hose from the heater core outlet.

Installation Procedure

  1. Install the outlet heater hose to the heater core outlet.
  2. Install the outlet heater hose to the outlet radiator hose connection.
  3. Install the heater hose clamps using the J 38185 .
  4. Fill the engine coolant. Refer to Cooling System Draining and Filling .
  5. Install the air cleaner assembly. Refer to Air Cleaner Assembly Replacement for the 4.3L engine or to Air Cleaner Assembly Replacement for the 4.8, 5.3, and 6.0L engine.

Heater Outlet Hose Replacement 6.6L - with Bypass Valve

Special Tools

J 38185 Hose Clamp Pliers

Removal Procedure

  1. Drain the engine coolant. Refer to Cooling System Draining and Filling.
  2. Remove the upper fan shroud. Refer to Engine Coolant Fan Upper Shroud Replacement.
  3. Remove the accumulator. Refer to Air Conditioning Accumulator Replacement

  4. Object Number: 1654213  Size: SH
  5. Reposition the heater hose clamps using the J 38185 .
  6. Remove the outlet heater hose from the outlet radiator hose connection.

  7. Object Number: 1654005  Size: SH
  8. Reposition the heater hose clamp using the J 38185 .
  9. Remove the outlet heater hose (2) from the coolant bypass valve.

Installation Procedure


    Object Number: 1654005  Size: SH
  1. Install the outlet heater hose (2) to the coolant bypass valve.
  2. Reposition the heater hose clamp using the J 38185 .
  3. Lower the vehicle.

  4. Object Number: 1654213  Size: SH
  5. Install the outlet heater hose to the outlet radiator hose connection.
  6. Reposition the heater hose clamp using the J 38185 .
  7. Install the accumulator. Refer to Air Conditioning Accumulator Replacement
  8. Fill the engine coolant. Refer to Cooling System Draining and Filling.
  9. Install the upper fan shroud. Refer to Engine Coolant Fan Upper Shroud Replacement.