Coolant Line/Hose: Service and Repair

Thermostat Housing Crossover Replacement (LLY/LBZ) (6.6L)

Removal Procedure

1. Remove the radiator fan. Refer to Fan Replacement (Service and Repair).
2. Remove the drive belt tensioner and generator bracket. Refer to Generator Bracket Replacement (4.8L/5.3L/6.0L) (Generator Bracket Replacement)Generator Bracket Replacement (6.6L) (Generator Bracket Replacement)Generator Bracket Replacement (4.3L) (Generator Bracket Replacement).
3. Remove the air conditioning (A/C) and power steering bracket. Refer to Air Conditioning (A/C) Compressor and Power Steering Pump Bracket Replacement (LLY, LBZ) (Service and Repair).




4. Remove the fuel line bolt and position the fuel line aside.




5. Compress the clamp and disconnect the turbocharger inlet cooling hose/pipe.




6. Remove the oil fill tube bolts and the oil fill tube.
7. Disconnect the coolant temperature sensor electrical connector.
8. Remove the exhaust gas recirculation (EGR) coolant pipe. Refer to Exhaust Gas Recirculation Coolant Hoses/Pipes Replacement (LLY/LBZ) (Exhaust Gas Recirculation Coolant Hoses/Pipes Replacement).




9. Remove the fuel pipe bracket bolt.
10. Disconnect the hose at the thermostat bypass pipe.
11. Disconnect the radiator inlet hose from the thermostat housing.
12. Remove the thermostat bypass bolts at the water pump.




13. Remove the 8 thermostat housing crossover bolts.
14. Remove the thermostat housing crossover.

Installation Procedure

1. Position the thermostat housing crossover.





Caution: Refer to Fastener Caution (Fastener Caution).

2. Install the 8 thermostat housing crossover bolts and tighten to 25 Nm (18 lb ft).
3. Install the thermostat bypass bolts to the water pump and tighten to 21 Nm (16 lb ft).
4. Install the radiator inlet hose to the thermostat housing.
5. Connect the hose to the thermostat bypass pipe.




6. Install the fuel pipe bracket bolt and tighten to 25 Nm (18 lb ft).
7. Install the EGR coolant pipe. Refer to Exhaust Gas Recirculation Coolant Hoses/Pipes Replacement (LLY/LBZ) (Exhaust Gas Recirculation Coolant Hoses/Pipes Replacement).
8. Connect the coolant temperature sensor electrical connector.




9. Install the oil fill tube bolts and the oil fill tube and tighten to 25 Nm (18 lb ft).




10. Compress the clamp and connect the turbocharger inlet cooling hose/pipe.




11. Position the fuel line and install the fuel line bolt.
12. Install the A/C and power steering bracket. Refer to Air Conditioning (A/C) Compressor and Power Steering Pump Bracket Replacement (LLY, LBZ) (Service and Repair).
13. Install the drive belt tensioner and generator bracket. Refer to Generator Bracket Replacement (4.8L/5.3L/6.0L) (Generator Bracket Replacement)Generator Bracket Replacement (6.6L) (Generator Bracket Replacement)Generator Bracket Replacement (4.3L) (Generator Bracket Replacement).
14. Instal the radiator fan. Refer to Fan Replacement (Service and Repair).