Engine Cooling System: Removal & Installation GMC Cutaway G3500

Cooling Layer Removal

Special Tools

J 38185 Hose Clamp Piers

1. Drain the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
2. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(ref-478462-S28963357882012061100000) .
3. Disconnect the negative battery cable. Refer to «Battery Negative Cable Disconnection and Connection»(ref-478456-S10745692822012061100000) .
4. Remove the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478507-S17677791602012061100000) .
5. Remove the surge tank. Refer to «Radiator Surge Tank Replacement»(ref-478473-S18271161932012061100000) .
6. Remove the front grille. Refer to «Grille Replacement (Base)»(ref-478447-S42854382812012061100000) , «Grille Replacement (Uplevel)»(ref-478447-S09643034972012061100000) .
7. Remove the front bumper. Refer to «Front Bumper Replacement»(ref-478472-S27390427202012061100000) .
8. Remove the charge air cooler inlet and outlet ducts. Refer to «Charge Air Cooler Inlet Pipe Replacement»(ref-478507-S12678002132012061100000) , and «Charge Air Cooler Outlet Pipe Replacement»(ref-478507-S01024729882012061100000) .
9. Using the «J 38185»(ref-478462-S20288722122012061100000) , reposition the radiator inlet hose clamp.
10. Disconnect the radiator inlet hose from the thermostat housing.
11. Raise and suitably support the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-478431-S02322330072012061100000) .
12. Remove the radiator outlet hose to radiator retaining clip and disconnect the hose.
13. Remove the upper transmission cooler line to radiator retaining clip and disconnect the line.
14. Remove the transmission cooler line to auxiliary transmission cooler retaining clip and disconnect the line.
15. Remove the evaporator to condenser hose retaining nut (1).
16. Disconnect the evaporator to condenser hose from the condenser.
17. Remove the suction hose bolt (1) from the air conditioning (A/C) compressor.
18. Disconnect the suction hose (4) from the A/C compressor.
19. Disconnect the wiring ground located at the RH fender.
20. Remove the RH fender to core support brace bolts and remove the brace.
21. Disconnect the wiring ground located at the LH fender.
22. Remove the LH fender to core support brace bolts and remove the brace.
23. Disconnect the wiring harness electrical connector at the underhood bused electrical center (UBEC).
24. Disconnect the hood release cable at the hood release latch. Position the cable aside.
25. Remove the positive battery cable nut from the junction block and disconnect the cable.
26. Remove the auxiliary positive cable nut from the junction block and disconnect the cable.
27. Remove the positive battery to UBEC cable nut from the junction block and disconnect the cable.
28. Remove the 4 LH and 4 RH core support bolts (1).
29. Remove the core support and the cooling layer.

Cooling Layer Installation

Special Tools

J 38185 Hose Clamp Pliers

1. Position the core support and the cooling layer to the vehicle.
2. Install the 4 LH and RH core support bolts (1) and tighten to 25 N.m (18 lb ft).
3. Position the positive battery to underhood bused electrical center (UBEC) cable to the junction block and install the nut then tighten to 8 N.m (71 lb in).
4. Position the auxiliary positive cable to the junction block and install the nut then tighten to 8 N.m (71 lb in).
5. Position the positive battery cable to the junction block and install the nut then tighten to 8 N.m (71 lb in).
6. Reposition and connect the hood release cable to the hood release latch.
7. Connect the wiring harness electrical connector at the UBEC.
8. Position the LH fender to core support brace and install the bolts.
9. Position the wiring ground to the LH fender and install the bolt and tighten to 9 N.m (80 lb in).
10. Position the RH fender to core support brace and install the bolts.
11. Position the wiring ground to the RH fender and install the bolt and tighten to 9 N.m (80 lb in).
12. Connect the suction hose (4) to the air conditioning (A/C) compressor.
13. Install the suction hose bolt (1) to the A/C compressor and tighten to 16 N.m (12 lb ft).
14. Position the evaporator to condenser hose to the condenser.
15. Install the evaporator to condenser hose nut (1) and tighten to 16 N.m (12 lb ft).
16. Position the transmission cooler line to the auxiliary transmission cooler and install the retaining clip.
17. Position the upper transmission cooler line to the radiator and install the retaining clip.
18. Lower the vehicle.
19. Position the radiator outlet hose to radiator and install the retaining clip.
20. Connect the radiator inlet hose to the radiator.
21. Using the «J 38185»(ref-478462-S20288722122012061100000) , reposition the radiator inlet hose clamp.
22. Install the charge air cooler inlet and outlet ducts. Refer to «Charge Air Cooler Inlet Pipe Replacement»(ref-478507-S12678002132012061100000) , and «Charge Air Cooler Outlet Pipe Replacement»(ref-478507-S01024729882012061100000) .
23. Install the front bumper. Refer to «Front Bumper Replacement»(ref-478472-S27390427202012061100000) .
24. Install the front grille. Refer to «Grille Replacement (Base)»(ref-478447-S42854382812012061100000) , «Grille Replacement (Uplevel)»(ref-478447-S09643034972012061100000) .
25. Install the surge tank. Refer to «Radiator Surge Tank Replacement»(ref-478473-S18271161932012061100000) .
26. Install the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478507-S17677791602012061100000) .
27. Connect the negative battery cable. Refer to «Battery Negative Cable Disconnection and Connection»(ref-478456-S10745692822012061100000) .
28. Recharge the refrigerant. Refer to «Refrigerant Recovery and Recharging»(ref-478462-S28963357882012061100000) .
29. Fill the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .

Removal Procedure

Special Tools

J 38185 Hose Clamp Pliers

1. Partially drain the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
2. Remove the overflow hose from the surge tank.
3. Using «J 38185»(ref-478462-S20288722122012061100000) , reposition the surge tank inlet hose clamp.
4. Remove the surge tank inlet hose from the surge tank.
5. Using «J 38185»(ref-478462-S20288722122012061100000) , reposition the surge tank outlet hose clamp.
6. Disconnect the surge tank outlet hose from the surge tank.
7. Remove the surge tank retaining bolt.
8. Tilt the surge tank assembly and disconnect the surge tank electrical connector.
9. Remove the surge tank from the vehicle.

Installation Procedure

1. Connect the surge tank electrical connector.
2. Install the surge tank to the vehicle.
3. Install the surge tank retaining bolt and tighten to 9 N.m (80 lb in).
4. Install the surge tank outlet hose to the surge tank.
5. Using «J 38185»(ref-478462-S20288722122012061100000) , reposition the surge tank outlet hose clamp.
6. Install the surge tank inlet hose to the surge tank.
7. Using «J 38185»(ref-478462-S20288722122012061100000) , reposition the surge tank inlet hose clamp.
8. Install the overflow hose to the surge tank.
9. Fill the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .

1. Partially drain the coolant. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
2. Disconnect the hose from the coolant recovery reservoir.
3. Remove the coolant recovery reservoir retaining screws.
4. Remove the coolant recovery reservoir.

1. Install the coolant recovery reservoir.
2. Install the coolant recovery reservoir retaining screws and tighten to 6 N.m (53 lb in).
3. Connect the hose to the coolant recovery reservoir.
4. Add coolant to reservoir. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .

Special Tools

J 38185 Hose Clamp Pliers

1. Partially drain the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
2. Using «J 38185»(ref-478462-S20288722122012061100000) reposition the surge tank inlet hose clamps.
3. Remove the surge tank inlet hose from the surge tank.
4. Remove the surge tank inlet hose from the radiator.

1. Install the surge tank inlet hose to the radiator.
2. Install the surge tank inlet hose to the surge tank.
3. Using «J 38185»(ref-478462-S20288722122012061100000) reposition the surge tank inlet hose clamp.
4. Fill the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .

1. Partially drain the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
2. Remove the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478505-S29445652162012061100000) .
3. Reposition the clamp from the radiator inlet using the «J 38185»(ref-478462-S20288722122012061100000) .
4. Reposition the clamp from the engine using the «J 38185»(ref-478462-S20288722122012061100000) .
5. Remove the radiator inlet hose from the radiator.
6. Remove the radiator inlet hose from the engine.
7. Remove the radiator inlet hose (5).

1. Install the radiator inlet hose (5).
2. Install the radiator inlet hose to the radiator.
3. Install the radiator inlet hose to the engine.
4. Position the hose clamp from the engine using the «J 38185»(ref-478462-S20288722122012061100000) .
5. Position the hose clamp from the radiator inlet engine using the «J 38185»(ref-478462-S20288722122012061100000) .
6. Install the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478505-S29445652162012061100000) .
7. Fill the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .

1. Drain the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
2. Remove the clamp at the radiator outlet using the «J 38185»(ref-478462-S20288722122012061100000) .
3. Remove the radiator outlet hose clamp at the engine using the «J 38185»(ref-478462-S20288722122012061100000) .
4. Remove the radiator outlet hose clamp at the coolant recovery reservoir using the «J 38185»(ref-478462-S20288722122012061100000) .
5. Disconnect the radiator outlet hose from the radiator. Refer to «Radiator Hose Quick Connect Fitting»(ref-478473-S23588746392012061100000) .
6. Disconnect the radiator outlet hose from the engine.
7. Remove the radiator outlet hose (4) from the engine compartment.

1. Install the radiator outlet hose (4) into the engine compartment.
2. Connect the radiator outlet hose to the engine.
3. Connect the radiator outlet hose to the radiator. Refer to «Radiator Hose Quick Connect Fitting»(ref-478473-S23588746392012061100000) .
4. Install the radiator outlet hose to the coolant recovery reservoir.
5. Install the radiator outlet hose clamp to the coolant recovery reservoir using the «J 38185»(ref-478462-S20288722122012061100000) .
6. Install the radiator outlet hose clamp to the engine using the «J 38185»(ref-478462-S20288722122012061100000) .
7. Fill the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .

1. Drain the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
2. Remove the clamp at the radiator outlet using the «J 38185»(ref-478462-S20288722122012061100000) .
3. Remove the radiator outlet hose clamp at the engine using the «J 38185»(ref-478462-S20288722122012061100000) .
4. Remove the radiator outlet hose clamp at the coolant recovery reservoir using the «J 38185»(ref-478462-S20288722122012061100000) .
5. Remove the radiator outlet hose from the coolant recovery reservoir.
6. Remove the radiator outlet hose from the radiator.
7. Remove the radiator outlet hose from the engine.
8. Remove the radiator outlet hose (4).

1. Install the radiator outlet hose (4).
2. Install the radiator outlet hose to the engine.
3. Install the radiator outlet hose to the radiator.
4. Install the radiator outlet hose to the coolant recovery reservoir.
5. Install the radiator outlet hose clamp to the coolant recovery reservoir using the «J 38185»(ref-478462-S20288722122012061100000) .
6. Install the radiator outlet hose clamp to the engine using the «J 38185»(ref-478462-S20288722122012061100000) .
7. Install the radiator outlet clamp to the radiator outlet using the «J 38185»(ref-478462-S20288722122012061100000) .
8. Fill the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .

1. Using a bent-tip screwdriver or equivalent, pull on one of the open ends of the retaining ring in order to rotate the retaining ring.
2. Rotate the retaining ring (3) around the quick connector until the retaining ring is out of position and can be completely removed.
3. Remove the radiator outlet hose (2) from the quick connector fitting at the radiator (1).

1. Hook one of the open ends of the retaining ring (3) in one of the slots in the quick connector.
2. Rotate the retaining ring (3) around the connector until the retaining ring is positioned with all 3 ears through the 3 slots.
3. Ensure the 3 retaining ring ears can be seen from the inside of the connector and the retaining ring can move freely in the slots.
4. Install the radiator outlet hose (2) onto the radiator quick connector fitting until a click is heard or felt. Pull back on the radiator outlet hose (2) to ensure a proper connection.

1. Drain the coolant from the reservoir. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
2. Remove the coolant recovery reservoir. Refer to «Coolant Recovery Reservoir Replacement»(ref-478473-S14152772412012061100000) .
3. Remove the vent hose from the throttle body.
4. Remove the vent hose from the radiator.
5. Remove the vent hose (1) from the vehicle.

1. Install the vent hose (1) to the vehicle.
2. Connect the vent hose to the radiator.
3. Connect the vent hose to the throttle body.
4. Install the coolant recovery reservoir. Refer to «Coolant Recovery Reservoir Replacement»(ref-478473-S14152772412012061100000) .
5. Fill the reservoir with coolant. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .

1. Disengage the plastic caps from the quick connect fittings. Pull the caps back along the pipe.
2. Using a bent-tip screwdriver or equivalent, pull on one of the open ends of the retaining ring in order to rotate the retaining ring.
3. Rotate the retaining ring around the quick connector until the retaining ring is out of position and can be completely removed. Discard the retaining rings.
4. Remove the engine oil cooler line from the quick connector fitting at the radiator. Pull the lines straight out from the connectors.
5. Clean all of the components in a suitable solvent, and dry them with compressed air.
6. Inspect the fittings, the connectors, the cooler lines, and the cooler for damage, distortion, or restriction. Replace parts as necessary.

1. Install a new retaining ring into each quick connector fitting.
2. Hook one of the open ends of the retaining ring in one of the slots in the quick connector.
3. Rotate the retaining ring around the connector until the retaining ring is positioned with all 3 ears through the 3 slots.
4. Ensure the 3 retaining ring ears can be seen from the inside of the connector and the retaining ring can move freely in the slots.
5. Install the engine oil cooler line into the quick connector fitting until a click is heard or felt. Pull back on the engine oil cooler lines to ensure a proper connection.
6. Snap the plastic cap onto the quick connect fitting.
7. Ensure that the plastic cap is fully seated against the fitting.
8. Ensure that no gap is present between the cap and the fitting.
9. Inspect and fill the engine oil to the proper level.

1. Disconnect the oil cooler hose (1) from the radiator. Refer to «Engine Oil Cooler Pipe/Hose Quick Connect Fitting Replacement»(ref-478473-S16695260772012061100000)
2. Gently, pull the oil cooler pipe fittings straight out from the radiator quick connect fittings.
3. Raise and suitably support the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-478431-S02322330072012061100000)
4. Remove the oil cooler hose bracket nut (1).
5. Remove the oil cooler hose adapter nut (2).
6. Remove the oil cooler hose assembly and seals.
7. Discard the seals.
8. Inspect the fittings, connectors and cooler hoses for damage or distortion.

1. Install the oil cooler hose assembly and a new seals.
2. Install the oil cooler hose adapter nut (2) and tighten to 12 N.m (106 lb in)
3. Install the oil cooler hose bracket nut (1) and tighten to 25 N.m (18 lb ft)
4. Connect the oil cooler hose (1) to the radiator. Refer to «Engine Oil Cooler Pipe/Hose Quick Connect Fitting Replacement»(ref-478473-S16695260772012061100000)
5. Pull back sharply on the cooler line in order to ensure that the cooler line is installed in the quick connect fitting.

The optional oil cooler is either an integral part of the radiator or a separate unit placed in front of the radiator. The cooler lines and hoses are serviceable.

1. Disconnect the cooler lines. Refer to «Engine Oil Cooler Pipe/Hose Quick Connect Fitting Replacement»(ref-478473-S16695260772012061100000) .
2. Open the oil cooler hose clip located on the lower fan shroud.
3. Remove the oil cooler hoses from the clip.
4. Gently, pull the oil cooler pipe fittings straight out from the radiator quick connect fittings.
5. Raise and suitably support the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-478431-S02322330072012061100000) .
6. Remove the oil cooler hose bracket bolt (1).
7. Remove the oil cooler hose adapter bolts (2).
8. Remove the oil cooler hose assembly and gasket.
9. Discard the gasket.
10. Inspect the fittings, connectors and cooler hoses for damage or distortion.

1. Install the oil cooler hose assembly and a new gasket.
2. Clean all dirt and oil from oil cooler hose adaptor bolt (2) threads and apply teflon pipe sealant to the threads. Refer to «Adhesives, Fluids, Lubricants, and Sealers»(ref-478473-S00654790842012061100000)
3. Install the oil cooler hose adapter bolts (2) and tighten to 12 N.m (106 lb in).
4. Install the oil cooler hose bracket bolt (1) and tighten to 25 N.m (18 lb ft).
5. Install the oil cooler hoses to the hose clip on the fan shroud.
6. Snap the oil cooler hose clip shut.
7. Connect the oil cooler lines. Refer to «Engine Oil Cooler Pipe/Hose Quick Connect Fitting Replacement»(ref-478473-S16695260772012061100000) .
8. Pull back sharply on the cooler line in order to ensure that the cooler line is installed in the quick connect fitting.

1. If a fan assembly fails, inspect the hub and the drive components. A fan assembly may fail due to an imbalance in the hub. This type of failure may not be the fault of the blades.
2. Remove the fan clutch assembly. Refer to «Fan Clutch Replacement»(ref-478473-S07171518262012061100000) .
3. Remove the fan to fan clutch retaining bolts.
4. Remove the fan from the fan clutch.

1. Install the fan to the fan clutch.
2. Install the fan to fan clutch retaining bolts and tighten to 23 N.m (17 lb ft).
3. Install the fan clutch assembly. Refer to «Fan Clutch Replacement»(ref-478473-S07171518262012061100000) .

1. Remove the upper fan shroud. Refer to «Engine Coolant Fan Upper Shroud Replacement (4.3L, 4.8L, 5.3L, 6.0L, 6.2L, 7.0L)»(ref-478473-S20241859372012061100000) .
2. Install the «J 41240-5A»(ref-478465) onto the fan clutch nut. Install the «J 46406»(ref-478465) in order to secure the pulley.
3. Remove the fan clutch assembly.
4. Inspect the following components for cracks, distortion, or other damage: The belt The hub The adapter The pulley
5. Remove the cooling fan from the fan clutch. Refer to «Fan Replacement»(ref-478473-S35393141892012061100000) .

1. Install the cooling fan to the fan clutch. Refer to «Fan Replacement»(ref-478473-S35393141892012061100000) .
2. Install the fan clutch assembly to the pulley.
3. Install the «J 41240-5A»(ref-478465) onto the fan clutch nut and tighten to 56 N.m (41 lb ft). Install the «J 46406»(ref-478465) in order to secure the pulley.
4. Install the upper fan shroud. Refer to «Engine Coolant Fan Upper Shroud Replacement (4.3L, 4.8L, 5.3L, 6.0L, 6.2L, 7.0L)»(ref-478473-S20241859372012061100000) .

1. Remove the fan clutch. Refer to «Fan Clutch Replacement»(ref-478473-S07171518262012061100000) .
2. Remove the drive belt. Refer to «Drive Belt Replacement»(ref-478531-S02419920182012061100000) .
3. Disconnect the camshaft position sensor connector.
4. Remove the cooling fan pulley bolts (2) and nuts (3).
5. Remove the cooling fan pulley (1) and the cooling fan pulley spacer (4).

1. Install the cooling fan pulley spacer (4) and the cooling fan pulley (1).
2. Install the cooling fan pulley bolts (2) and nuts (3).
3. Tighten the cooling fan pulley bolts (1) and nuts (2) in sequence to 50 N.m (37 lb ft).
4. Connect the camshaft position sensor connector.
5. Install the drive belt. Refer to «Drive Belt Replacement»(ref-478531-S02419920182012061100000) .
6. Install the fan clutch. Refer to «Fan Clutch Replacement»(ref-478473-S07171518262012061100000) .

Scheme 1

Turbocharger Coolant Return Pipe Replacement

1. Remove the turbocharger. Refer to «Turbocharger Replacement»(ref-478531-S19600206272012061100000) .
2. Remove the exhaust gas recirculation (EGR) valve cooler assembly. Refer to «Exhaust Gas Recirculation Valve Cooler Replacement (LGH)»(ref-478473-S37962903982012061100000) .
3. Remove the generator mounting bracket. Refer to «Generator Bracket Replacement (V8)»(ref-478456-S37792142572012061100000) , «Generator Bracket Replacement (V6)»(ref-478456-S14795138002012061100000) .
4. Remove the cooling fan clutch. Refer to «Fan Clutch Replacement»(ref-478473-S07171518262012061100000) .
5. Reposition the hose clamp and move the turbocharger coolant return hose (1) away from the turbocharger coolant return pipe (2).
6. Remove the turbocharger coolant return pipe retainer bolt (1).
7. Remove the turbocharger coolant return pipe retainer bolt (1) attached to the right front valve cover.
8. Remove the turbocharger coolant return pipe retainer bolt (1) on top of the engine.
9. Remove the turbocharger coolant return pipe (3) and hose (2) from the engine.
10. Replace any worn or damaged hoses.

1. Position the turbocharger coolant return pipe onto engine.
2. Install the turbocharger coolant return pipe retainer bolt (1). Tighten Tighten the bolt to 25 N.m (18 lb ft).
3. Install the turbocharger coolant return hose (1) onto the turbocharger coolant return pipe (2)
4. Install the turbocharger coolant return to the pipe retainer bolt (1) onto the right front valve cover. Tighten Tighten the bolt to 25 N.m (18 lb ft).
5. Install the turbocharger coolant return pipe retainer bolt (1). Tighten Tighten the bolt to 25 N.m (18 lb ft).
6. Install the turbocharger. Refer to «Turbocharger Replacement»(ref-478531-S19600206272012061100000) .
7. Install the EGR valve cooler assembly. Refer to «Exhaust Gas Recirculation Valve Cooler Replacement (LGH)»(ref-478473-S37962903982012061100000) .
8. Install the generator mounting bracket. Refer to «Generator Bracket Replacement (V8)»(ref-478456-S37792142572012061100000) , «Generator Bracket Replacement (V6)»(ref-478456-S14795138002012061100000) .
9. Install the cooling fan clutch. Refer to «Fan Clutch Replacement»(ref-478473-S07171518262012061100000) .

1. Remove the engine cover. Refer to «Engine Cover Replacement»(ref-478450-S15372444062012061100000) .
2. Drain the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
3. Remove the positive crankcase ventilation hose. Refer to «Positive Crankcase Ventilation Hose/Pipe/Tube Replacement (Oil Separator to Oil Pan)»(ref-478531-S00261676772012061100000) , «Positive Crankcase Ventilation Hose/Pipe/Tube Replacement (Regulator Valve to Separator)»(ref-478531-S16474364882012061100000) .
4. Compress the clamps (1) and disconnect the turbocharger coolant feed hose (2) from the turbocharger coolant feed pipes (3).
5. Remove the turbocharger coolant feed bolt (1) and washers (2), from the turbocharger.
6. Remove the turbocharger coolant feed pipe retainer bolt (3).
7. Remove the turbocharger coolant feed pipe (4).
8. Remove the turbocharger coolant feed pipe retainer bolt (1).
9. Slide the hose clamp (4) upward and remove the turbocharger coolant feed pipe (2) and hose (3) from the engine.
10. Slide the hose clamp (1) downward and remove the turbocharger coolant feed hose (3) from the turbocharger coolant feed pipe (2).

1. Position the turbocharger inlet cooling hose/pipe to the vehicle.
2. Using NEW brass seals (2), finger-tighten the turbocharger coolant feed pipe bolt (1) to the turbocharger.
3. Install the turbocharger coolant feed pipe retainer bolt (3) and tighten to 10 N.m (89 lb in).
4. Tighten the turbocharger coolant feed pipe bolt (1) to 25 N.m (18 lb ft).
5. Install the turbocharger coolant feed hose (2) to the turbocharger coolant feed pipes (3).
6. Slide the turbocharger coolant feed hose (3) onto the thermostat housing and secure with the hose clamps (4).
7. Install the turbocharger coolant feed pipe retainer bolt (1) and tighten to 10 N.m (89 lb in).
8. Fill the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
9. Install the engine cover. Refer to «Engine Cover Replacement»(ref-478450-S15372444062012061100000) .
10. Install the positive crankcase ventilation hose. Refer to «Positive Crankcase Ventilation Hose/Pipe/Tube Replacement (Oil Separator to Oil Pan)»(ref-478531-S00261676772012061100000) , «Positive Crankcase Ventilation Hose/Pipe/Tube Replacement (Regulator Valve to Separator)»(ref-478531-S16474364882012061100000) .

Scheme 2

Exhaust Gas Recirculation Valve Cooler Replacement (LGH)

Scheme 3

Exhaust Gas Recirculation Coolant Hoses/Pipes Replacement (LGH)

Note. The thermostat is not serviceable separately. The water pump inlet and thermostat must be replaced as an assembly.

1. Remove the bolt from the coolant recovery reservoir and reposition.
2. Remove air cleaner assembly.
3. Remove the radiator outlet hose. Refer to «Radiator Outlet Hose Replacement (LR4, LM7, LQ4)»(ref-478473-S40969312762012061100000) , «Radiator Outlet Hose Replacement (LU3)»(ref-478473-S17280511092012061100000) .
4. Remove the water pump inlet bolts.
5. Remove the water pump inlet and thermostat from the water pump.

1. Install the thermostat and water pump inlet to the water pump.
2. Install the water pump inlet bolts and tighten to 15 N.m (11 lb ft).
3. Install the radiator outlet hose. Refer to «Radiator Outlet Hose Replacement (LR4, LM7, LQ4)»(ref-478473-S40969312762012061100000) , «Radiator Outlet Hose Replacement (LU3)»(ref-478473-S17280511092012061100000) .
4. Install the air cleaner assembly.
5. Install the coolant recovery reservoir and bolt and tighten to 11 N.m (97 lb in).

1. Remove the air cleaner and the duct assembly. Refer to «Air Cleaner Outlet Resonator Replacement»(ref-478505-S32161210542012061100000) .
2. Partially drain the coolant. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
3. Remove the coolant recovery reservoir. Refer to «Coolant Recovery Reservoir Replacement»(ref-478473-S14152772412012061100000) .
4. Disconnect the radiator hose from the thermostat housing.
5. Remove the bolts attaching the thermostat housing to the thermostat.
6. Remove the thermostat housing.
7. Remove the thermostat.
8. Clean the gasket mating surfaces.

1. Install the thermostat.
2. Install the thermostat housing to the intake manifold.
3. Install the bolts to the housing and tighten to 25 N.m (18 lb ft).
4. Connect the radiator hose to the thermostat housing.
5. Install the coolant recovery reservoir. Refer to «Coolant Recovery Reservoir Replacement»(ref-478473-S14152772412012061100000) .
6. Install the air cleaner and the duct. Refer to «Air Cleaner Outlet Resonator Replacement»(ref-478505-S32161210542012061100000) .
7. Refill the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
8. Bleed the air from the cooling system.
9. Inspect the thermostat housing and the gasket for coolant leaks.

1. Remove the radiator fan. Refer to «Fan Replacement»(ref-478473-S35393141892012061100000) .
2. Remove the radiator inlet hose. Refer to «Radiator Inlet Hose Replacement (LU3, LR4, LM7, LQ4)»(ref-478473-S25838272292012061100000)
3. Remove the fuel return canister from the clip retainer at the top of the thermostat housing.
4. Remove the drive belt tensioner. Refer to «Drive Belt Replacement»(ref-478531-S02419920182012061100000) .
5. Remove the generator bracket. Refer to «Generator Bracket Replacement (V8)»(ref-478456-S37792142572012061100000) , «Generator Bracket Replacement (V6)»(ref-478456-S14795138002012061100000)
6. Remove the air conditioning (A/C) and power steering bracket. .
7. Remove the fuel pressure valve bolt (1) and reposition the fuel line (2).
8. Disconnect the engine coolant temperature sensor electrical connector (1).
9. Remove the turbocharger coolant feed hose (2) .
10. Remove the oil fill tube bolt (3); the oil fill tube retainer bracket bolt (4) and the oil fill tube (5).
11. Disconnect the turbocharger coolant return hose (1) at the thermostat bypass pipe (3).
12. Remove the thermostat bypass bolts (2) at the water pump and remove the thermostat bypass pipe (3).
13. Remove the thermostat housing crossover bolts (1) and nuts (2).
14. Remove the thermostat housing crossover pipe (4) and gaskets (3).

1. Position the thermostat housing crossover with NEW gaskets.
2. Install the thermostat housing crossover bolts (1) and nuts (2).Tighten to 25 N.m (18 lb ft).
3. Install the thermostat bypass bolts (2) to the water pump and tighten to 21 N.m (16 lb ft).
4. Connect the turbocharger coolant return hose (1) to the thermostat bypass pipe (3).
5. Install the oil fill tube bolt (3) and tighten to 25 N.m (18 lb ft).
6. Install the oil fill tube bracket bolt (4) and tighten to 25 N.m (18 lb ft)
7. Install the turbocharger coolant feed hose (2) and the engine coolant temperature sensor connector (1).
8. Install the fuel return line canister into the clip retainer at the top of the thermostat housing.
9. Install the fuel pressure valve bolt (1) and tighten to 25 N.m (18 lb ft)
10. Install the A/C compressor and power steering bracket.
11. Install the generator bracket. Refer to «Generator Bracket Replacement (V8)»(ref-478456-S37792142572012061100000) , «Generator Bracket Replacement (V6)»(ref-478456-S14795138002012061100000) .
12. Install the drive belt tensioner. Refer to «Drive Belt Replacement»(ref-478531-S02419920182012061100000)
13. Install the radiator fan. Refer to «Fan Replacement»(ref-478473-S35393141892012061100000) .
14. Install the radiator inlet hose. Refer to «Radiator Inlet Hose Replacement (LU3, LR4, LM7, LQ4)»(ref-478473-S25838272292012061100000) .

1. Remove the air cleaner outlet duct. Refer to «Air Cleaner Resonator Outlet Duct Replacement»(ref-478506-S24536390282012061100000) .
2. Drain the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
3. Reposition the radiator vent inlet hose clamp (1) at the coolant air bleed pipe fitting.
4. Remove the radiator vent inlet hose (2) from the coolant air bleed pipe fitting.
5. Remove the coolant air bleed pipe bolts (309) (intake manifold shown removed for clarity).
6. Remove the coolant air bleed pipe (307) and seals (308).
7. Remove the coolant air bleed cover bolts (312), if required.
8. Remove the coolant air bleed covers (313) and seals (308), if required.
9. Remove the seals (308) from the coolant air bleed pipe and/or covers.
10. Discard the seals.

1. Install the seals onto the coolant air bleed pipe and/or covers.
2. Install the coolant air bleed pipe (307) and seals (308) onto the cylinder heads.
3. Install the coolant air bleed pipe bolts (309) and tighten to 12 N.m (106 lb in).
4. Install the coolant air bleed covers (313) and seals (308), if required.
5. Install the coolant air bleed cover bolts (312), if required and tighten to 12 N.m (106 lb in).
6. Install the radiator vent inlet hose (2) to the coolant air bleed pipe fitting.
7. Position the radiator vent inlet hose clamp (1) at the coolant air bleed pipe fitting.
8. Install the air cleaner outlet duct. Refer to «Air Cleaner Resonator Outlet Duct Replacement»(ref-478506-S24536390282012061100000) .
9. Fill the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .

1. Remove the air cleaner outlet duct. Refer to «Air Cleaner Resonator Outlet Duct Replacement»(ref-478506-S24536390282012061100000) .
2. Drain the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
3. Reposition the radiator vent inlet hose clamp (1) at the coolant air bleed pipe fitting.
4. Remove the radiator vent inlet hose (2) from the coolant air bleed pipe fitting.
5. Remove the coolant air bleed pipe bolts (309) (intake manifold shown removed for clarity).
6. Remove the coolant air bleed pipe (307) and seals (308).
7. Remove the coolant air bleed cover bolts (312), if required.
8. Remove the coolant air bleed covers (313) and seals (308), if required.
9. Remove the seals (308) from the coolant air bleed pipe and/or covers.
10. Discard the seals.

1. Install the seals onto the coolant air bleed pipe and/or covers.
2. Install the coolant air bleed pipe (307) and seals (308) onto the cylinder heads.
3. Install the coolant air bleed pipe bolts (309) and tighten to 12 N.m (106 lb in).
4. Install the coolant air bleed covers (313) and seals (308), if required.
5. Install the coolant air bleed cover bolts (312), if required and tighten to 12 N.m (106 lb in).
6. Install the radiator vent inlet hose (2) to the coolant air bleed pipe fitting.
7. Position the radiator vent inlet hose clamp (1) at the coolant air bleed pipe fitting.
8. Install the air cleaner outlet duct. Refer to «Air Cleaner Resonator Outlet Duct Replacement»(ref-478506-S24536390282012061100000) .
9. Fill the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .

Scheme 4

Thermostat Bypass Pipe Replacement (LGH)

1. Remove the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478505-S29445652162012061100000) .
2. Remove the air cleaner outlet resonator duct. Refer to «Air Cleaner Outlet Resonator Replacement»(ref-478505-S32161210542012061100000) .
3. Drain the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
4. Remove the cooling fan.
5. Remove the drive belt. Refer to «Drive Belt Replacement»(ref-478432-S19004765682012061100000) .
6. Reposition the radiator outlet hose clamps at the surge tank and water pump.
7. Remove the radiator outlet hose from the surge tank.
8. Remove the radiator outlet hose from the water pump.
9. Reposition the water pump inlet hose clamps.
10. Remove the water pump inlet hose.
11. Using «J 41240»(ref-478432-S25313633812012061100000) to hold the water pump pulley, remove the water pump pulley bolts.
12. Remove the water pump bolts.
13. Remove the water pump.
14. Remove and discard the water pump gaskets.
15. Clean and inspect the water pump, if necessary. Refer to «Water Pump Cleaning and Inspection»(ref-478432-S00825248362012061100000) .

1. If reusing the fasteners, apply sealant GM P/N 12346004 (Canadian P/N 10953480), or equivalent to the threads of the water pump bolts.
2. Install NEW water pump gaskets and the water pump. CAUTION: Refer to «Fastener Caution»(ref-478430-S14976206932012061100000) .
3. Install the water pump bolts and tighten to 45 N.m (33 lb ft).
4. Using «J 41240»(ref-478432-S25313633812012061100000) to hold the water pump pulley, install the water pump pulley bolts and tighten to 25 N.m (18 lb ft).
5. Install the water pump inlet hose.
6. Position the water pump inlet hose clamps.
7. Install the radiator outlet hose to the water pump.
8. Install the radiator outlet hose to the surge tank.
9. Position the radiator outlet hose clamps at the surge tank and water pump.
10. Install the drive belt. Refer to «Drive Belt Replacement»(ref-478432-S19004765682012061100000) .
11. Install the cooling fan.
12. Install the air cleaner outlet resonator duct. Refer to «Air Cleaner Outlet Resonator Replacement»(ref-478505-S32161210542012061100000) .
13. Install the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478505-S29445652162012061100000) .
14. Fill the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
15. Inspect the cooling system for leaks.

1. Remove the air cleaner outlet assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478506-S14748950762012061100000) .
2. Drain the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
3. Reposition the radiator vent inlet hose clamp (1) at the coolant air bleed pipe fitting.
4. Remove the radiator vent inlet hose (2) from the coolant air bleed pipe fitting.
5. Reposition the radiator inlet hose clamp (3) at the water pump.
6. Remove the radiator inlet hose from the water pump.
7. Reposition the radiator inlet hose and vent inlet hose out of the way.
8. Remove the accessory drive belt. Refer to «Drive Belt Replacement - Accessory»(ref-478530-S30056528102012061100000) .
9. Reposition the radiator outlet hose clamp at the water pump.
10. Remove the radiator outlet hose from the water pump.
11. Reposition the outlet hose out of the way.
12. Reposition the radiator surge tank outlet hose clamp (1) at the water pump.
13. Remove the radiator surge tank outlet hose (2) from the water pump.
14. Reposition the outlet hose out of the way.
15. Reposition the heater inlet hose clamp (1) at the water pump.
16. Remove the heater inlet hose (2) from the water pump.
17. Reposition the inlet hose out of the way.
18. Remove the water pump bolts (301).
19. Remove the water pump (300) and gaskets (309). Discard the gaskets.

Note. All gaskets surfaces are to be free of oil or other foreign material during assembly.

1. Position the water pump (300) and NEW gaskets (306) to the engine block.
2. Install the water pump bolts (301). Tighten the bolts a first pass to 15 N.m (11 lb ft). Tighten the bolts a final pass to 30 N.m (22 lb ft).
3. Position and install the heater inlet hose (2) to the water pump.
4. Position the heater inlet hose clamp (1) at the water pump.
5. Position and install the radiator surge tank outlet hose (2) to the water pump.
6. Position the radiator surge tank outlet hose clamp (1) at the water pump.
7. Position and install the radiator outlet hose to the water pump.
8. Position the radiator outlet hose clamp at the water pump.
9. Install the accessory drive belt. Refer to «Drive Belt Replacement - Accessory»(ref-478530-S30056528102012061100000) .
10. Position the radiator inlet hose and vent inlet hose to the correct position.
11. Install the radiator inlet hose to the water pump.
12. Position the radiator inlet hose clamp (3) at the water pump.
13. Install the radiator vent inlet hose (2) to the coolant air bleed pipe fitting.
14. Position the radiator vent inlet hose clamp (1) at the coolant air bleed pipe fitting.
15. Fill the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
16. Install the air cleaner outlet assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478506-S14748950762012061100000) .

1. Remove the air cleaner outlet assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478506-S14748950762012061100000) .
2. Drain the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
3. Reposition the radiator vent inlet hose clamp (1) at the coolant air bleed pipe fitting.
4. Remove the radiator vent inlet hose (2) from the coolant air bleed pipe fitting.
5. Reposition the radiator inlet hose clamp (3) at the water pump.
6. Remove the radiator inlet hose from the water pump.
7. Reposition the radiator inlet hose and vent inlet hose out of the way.
8. Remove the accessory drive belt. Refer to «Drive Belt Replacement - Accessory»(ref-478530-S30056528102012061100000) .
9. Reposition the radiator outlet hose clamp at the water pump.
10. Remove the radiator outlet hose from the water pump.
11. Reposition the outlet hose out of the way.
12. Reposition the radiator surge tank outlet hose clamp at the water pump (1).
13. Remove the radiator surge tank outlet hose (2) from the water pump.
14. Reposition the outlet hose out of the way.
15. Reposition the heater inlet hose clamp (1) at the water pump.
16. Remove the heater inlet hose (2) from the water pump.
17. Reposition the inlet hose out of the way.
18. Remove the water pump bolts (301).
19. Remove the water pump (300) and gaskets (309). Discard the gaskets.

Note. All gaskets surfaces are to be free of oil or other foreign material during assembly.

1. Inspect the drained coolant for sand or other debris, flush the system as needed. Refer to «Flushing»(ref-478473-S00551640702012061100000) .
2. Inspect and clear the radiator vent hose fitting, if necessary. There is a small 2.0 mm (0.080 in) orifice (vent hose fitting) in the neck of the radiator where the coolant vent hose from the engine attaches to the radiator.
3. Position the water pump (300) and NEW gaskets (306) to the engine block.
4. Install the water pump bolts (301). Tighten the bolts a first pass to 15 N.m (11 lb ft). Tighten the bolts a final pass to 30 N.m (22 lb ft).
5. Position and install the heater inlet hose (2) to the water pump.
6. Position the heater inlet hose clamp (1) at the water pump.
7. Position and install the radiator surge tank outlet hose (2) to the water pump.
8. Position the radiator surge tank outlet hose clamp at the water pump (1).
9. Position and install the radiator outlet hose to the water pump.
10. Position the radiator outlet hose clamp at the water pump.
11. Install the accessory drive belt. Refer to «Drive Belt Replacement - Accessory»(ref-478530-S30056528102012061100000) .
12. Position the radiator inlet hose and vent inlet hose to the correct position.
13. Install the radiator inlet hose to the water pump.
14. Position the radiator inlet hose clamp (3) at the water pump.
15. Install the radiator vent inlet hose (2) to the coolant air bleed pipe fitting.
16. Position the radiator vent inlet hose clamp (1) at the coolant air bleed pipe fitting.
17. Fill the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
18. Install the air cleaner outlet assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478506-S14748950762012061100000) .

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-478431-S02322330072012061100000) .
2. Remove the positive crankcase ventilation pipe bracket bolt (5).
3. Remove the positive crankcase ventilation pipe bolt (4) and reposition the pipe (6).
4. Remove the water pump to water pump outlet pipe nuts (1) from the studs (2).
5. Remove the water pump to water pump outlet pipe studs (2) and discard the gasket (3).
6. Remove the five oil filter adapter and oil cooler assembly bolts (1) and the water pump outlet pipe (3).
7. Remove the water pump outlet pipe (1) from the oil filter adapter and oil cooler assembly (3).

1. Install a NEW water pump outlet pipe O-ring (2) onto the pipe and lubricate the O-ring seal with engine coolant.
2. Install new O-rings (2) to the oil filter adapter and oil cooler assembly. Lubricate the O-rings with engine oil.
3. Apply sealer to the O-ring sealing area (1). Refer to «Adhesives, Fluids, Lubricants, and Sealers»(ref-478544-S18377980292012061100000)
4. Install the oil cooler assembly (2) and the water pump outlet pipe (3), to the engine block. Tighten the bolts (1) to 25 N.m (18 lb ft).
5. Position a NEW water pump outlet pipe gasket (3) to the water pump. Install the water pump outlet pipe to the water pump outlet pipe studs (1) and tighten the nuts (1) to 25 N.m (18 lb ft).
6. Install the positive crankcase ventilation pipe (6) with bolt (4) and the retainer bracket bolt (5). Tighten to 12 N.m (106 lb in).
7. Lower the vehicle.

Scheme 5

Engine Coolant Temperature Sensor Replacement

1. Remove the coolant recovery reservoir. Refer to «Coolant Recovery Reservoir Replacement»(ref-478473-S14152772412012061100000) .
2. Remove the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478505-S29445652162012061100000) , for the 4.3L engine or «Air Cleaner Assembly Replacement»(ref-478506-S14748950762012061100000) for the 4.8L, 5.3L, 6.0L, 6.2L, and 7.0L engines.
3. Remove the air cleaner outlet resonator. Refer to «Air Cleaner Outlet Resonator Replacement»(ref-478505-S32161210542012061100000) , for the 4.3L engine or «Air Cleaner Resonator Outlet Duct Replacement»(ref-478506-S24536390282012061100000) for the 4.8L, 5.3L, 6.0L, 6.2L, and 7.0L engines.
4. For the 4.3L engine, remove the air conditioning (A/C) suction hose. Refer to «Suction Hose Replacement (4.8L, 5.3L, 6.0L)»(ref-478462-S13018404852012061100000) for the 4.3L engine.
5. For the 4.8L, 5.3L and 6.0L engine, remove the radiator inlet hose. Refer to «Radiator Inlet Hose Replacement (LU3, LR4, LM7, LQ4)»(ref-478473-S25838272292012061100000) .
6. Remove the battery cable from the fan shroud clips and reposition.
7. Remove the mass air flow (MAF) sensor wire from the fan shroud clip and reposition.
8. Remove the transmission oil lever indicator.
9. Remove the fan shroud bolts (1, 3, 4).
10. Remove the fan shroud (2, 5).

1. Install the fan shroud (2, 5).
2. Install the fan shroud bolts (1, 3, 4) and tighten to 6 N.m (53 lb in).
3. Install the transmission oil lever indicator.
4. Install the MAF sensor wire to the fan shroud clip.
5. Install the battery cable to the fan shroud clips.
6. For the 4.3L engine, install the A/C suction hose. Refer to «Suction Hose Replacement (4.8L, 5.3L, 6.0L)»(ref-478462-S13018404852012061100000) for the 4.3L engine.
7. For the 4.8L, 5.3L and 6.0L engine, install the radiator inlet hose. Refer to «Radiator Inlet Hose Replacement (LU3, LR4, LM7, LQ4)»(ref-478473-S25838272292012061100000) .
8. Install the air cleaner outlet resonator. Refer to «Air Cleaner Outlet Resonator Replacement»(ref-478505-S32161210542012061100000) , for the 4.3L engine or «Air Cleaner Resonator Outlet Duct Replacement»(ref-478506-S24536390282012061100000) for the 4.8L, 5.3L, 6.0L, 6.2L, and 7.0L engines.
9. Install the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478506-S14748950762012061100000) , for the 4.8L, 5.3L, 6.0L, 6.2L, and 7.0L engines or «Air Cleaner Assembly Replacement»(ref-478505-S29445652162012061100000) for the 4.3L engine.
10. Install the coolant recovery reservoir. Refer to «Coolant Recovery Reservoir Replacement»(ref-478473-S14152772412012061100000) .

1. Remove the coolant recovery reservoir. Refer to «Coolant Recovery Reservoir Replacement»(ref-478473-S14152772412012061100000) .
2. Remove the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478506-S14748950762012061100000) , for the 4.8L, 5.3L, 6.0L, 6.2L, 7.0L engines or «Air Cleaner Assembly Replacement»(ref-478505-S29445652162012061100000) for the 4.3L engine.
3. Remove the fan shroud bolts (1,3,4).
4. Remove the fan shroud (2,5).

1. Install the fan shroud (2,5).
2. Install the fan shroud bolts (1,3,4) and tighten to 6 N.m (53 lb in).
3. Install the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478506-S14748950762012061100000) , for the 4.8L, 5.3L, 6.0L, 6.2L, 7.0L engines or «Air Cleaner Assembly Replacement»(ref-478505-S29445652162012061100000) for the 4.3L engine.
4. Install the coolant recovery reservoir. Refer to «Coolant Recovery Reservoir Replacement»(ref-478473-S14152772412012061100000) .

Note. Always install a new set of insulators when replacing a radiator. Used insulators may be worn or too large for the new radiator. These conditions may cause the new radiator to be loose.

1. Remove the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478506-S14748950762012061100000) , for the 4.8L, 5.3L, 6.0L, 6.2L, 7.0L engines or «Air Cleaner Assembly Replacement»(ref-478505-S29445652162012061100000) for the 4.3L engine.
2. Remove the coolant recovery reservoir. Refer to «Coolant Recovery Reservoir Replacement»(ref-478473-S14152772412012061100000) .
3. Remove the clamp at the radiator inlet using the «J 38185»(ref-478462-S20288722122012061100000) .
4. Remove the radiator inlet hose (5) from the radiator.
5. Remove the outlet heater hose clamp at the radiator using the «J 38185»(ref-478462-S20288722122012061100000) .
6. Remove the outlet heater hose (2) from the radiator.
7. Remove the automatic transmission cooler lines. Refer to «Transmission Fluid Cooler Hose/Pipe Quick-Connect Fitting Disconnection and Connection»(ref-478482-S05417159812012061100000) , for the 4L60-E/4L65-E/4L70-E transmission or «Transmission Fluid Cooler Hose/Pipe Quick-Connect Fitting Disconnection and Connection»(ref-478501-S08068495782012061100000) for the 6L90 transmission.
8. Remove the engine oil cooler lines. Refer to «Engine Oil Cooler Pipe/Hose Quick Connect Fitting Replacement»(ref-478473-S16695260772012061100000) .
9. Remove the fan shroud bolts (1) from the top of the radiator support.
10. Remove the fan shroud bolts (3) from the sides of the fan shroud.
11. Remove the radiator (2).
12. Remove the radiator insulators (1, 3).
13. Inspect the following components: The radiator The insulators The hoses and clamps The mounting hardware Replace the components as necessary.

1. Install the radiator insulators (1, 3).
2. Install the radiator (2).
3. Install the fan shroud bolts (1) to the top of the radiator support and tighten to 6 N.m (53 lb in).
4. Install the fan shroud bolts (3) to the sides of the fan shroud and tighten to 6 N.m (53 lb in).
5. Install the engine oil cooler lines. Refer to «Engine Oil Cooler Pipe/Hose Quick Connect Fitting Replacement»(ref-478473-S16695260772012061100000) .
6. Install the automatic transmission oil cooler lines. Refer to «Transmission Fluid Cooler Hose/Pipe Quick-Connect Fitting Disconnection and Connection»(ref-478482-S05417159812012061100000) , for the 4L60-E/4L65-E/4L70-E transmission or «Transmission Fluid Cooler Hose/Pipe Quick-Connect Fitting Disconnection and Connection»(ref-478501-S08068495782012061100000) for the 6L90 transmission.
7. Install the radiator inlet hose (5) to the radiator.
8. Install the hose clamp at the radiator inlet housing using the «J 38185»(ref-478462-S20288722122012061100000) .
9. Install the outlet heater hose (2).
10. Install the outlet heater hose clamp using the «J 39529»(ref-478473-S06617945892012061100000) .
11. Install the coolant recovery reservoir. Refer to «Coolant Recovery Reservoir Replacement»(ref-478473-S14152772412012061100000) .
12. Install the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478506-S14748950762012061100000) , for the 4.8L, 5.3L, 6.0L, 6.2L, 7.0L engines or «Air Cleaner Assembly Replacement»(ref-478505-S29445652162012061100000) for the 4.3L engine.
13. Inspect the automatic transmission fluid level. Refer to «Approximate Fluid Capacities»(ref-478438-S27013746372012061100000) .
14. Inspect the engine oil level. Refer to «Approximate Fluid Capacities»(ref-478438-S27013746372012061100000) .

Note. Always install a new set of insulators when replacing a radiator. Used insulators may be worn or too large for the new radiator. These conditions may cause the new radiator to be loose.

1. Remove the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478507-S17677791602012061100000) .
2. Remove the upper radiator baffle.
3. Remove the surge tank. Refer to «Radiator Surge Tank Replacement»(ref-478473-S18271161932012061100000) .
4. Remove battery. Refer to «Battery Replacement (Primary)»(ref-478456-S12007866262012061100000) .
5. Remove the charged air cooler inlet pipe. Refer to «Charge Air Cooler Inlet Pipe Replacement»(ref-478507-S12678002132012061100000) .
6. Remove the clamp at the radiator inlet using the «J 38185»(ref-478462-S20288722122012061100000) .
7. Remove the radiator inlet hose (5) from the radiator.
8. Remove the outlet heater hose clamp at the radiator using the «J 38185»(ref-478462-S20288722122012061100000) .
9. Remove the outlet heater hose (2) from the radiator.
10. Remove the automatic transmission cooler lines. Refer to «Transmission Fluid Cooler Hose/Pipe Quick-Connect Fitting Disconnection and Connection»(ref-478482-S05417159812012061100000) , for the 4L60-E/4L65-E/4L70-E transmissions or «Transmission Fluid Cooler Hose/Pipe Quick-Connect Fitting Disconnection and Connection»(ref-478501-S08068495782012061100000) for the 6L90 transmissions.
11. Remove the engine oil cooler lines. Refer to «Engine Oil Cooler Pipe/Hose Quick Connect Fitting Replacement»(ref-478473-S16695260772012061100000) .
12. Remove the engine oil fill tube.
13. Remove intake manifold tube. Refer to «Intake Manifold Tube Replacement»(ref-478531-S22201583172012061100000) .
14. Remove the upper radiator baffle. Remove the fan shroud bolts (1) from the top of the radiator support.
15. Remove the fan shroud bolts (3) from the sides of the fan shroud.
16. Remove the radiator mounting bolts from the charged air cooler.
17. Remove the charge air cooler bolts to core support.
18. Remove the radiator and charge air cooler as assembly.
19. Remove radiator bolts to charge air cooler.
20. Remove the radiator insulators.
21. Inspect the following components: The radiator The insulators The hoses and clamps The mounting hardware Replace the components as necessary.

1. Install the radiator insulators.
2. Install the radiator to the charge air cooler and tighten the bolts to 6 N.m (53 lb in).
3. Install the radiator and charge air cooler as an assembly.
4. Install the radiator mounting bolts to the charged air cooler and tighten to 6 N.m (53 lb in).
5. Install the fan shroud bolts (1) to the top of the radiator support and tighten to 6 N.m (53 lb in).
6. Install the fan shroud bolts (3) to the sides of the fan shroud and tighten to 6 N.m (53 lb in).
7. Install the engine oil cooler lines. Refer to «Engine Oil Cooler Pipe/Hose Quick Connect Fitting Replacement»(ref-478473-S16695260772012061100000) .
8. Install the automatic transmission oil cooler lines. Refer to «Transmission Fluid Cooler Hose/Pipe Quick-Connect Fitting Disconnection and Connection»(ref-478482-S05417159812012061100000) , for the 4L60-E/4L65-E/4L70-E transmissions or «Transmission Fluid Cooler Hose/Pipe Quick-Connect Fitting Disconnection and Connection»(ref-478501-S08068495782012061100000) for the 6L90 transmissions.
9. Install the radiator inlet hose (5) to the radiator.
10. Install the hose clamp at the radiator inlet housing using the «J 38185»(ref-478462-S20288722122012061100000) .
11. Install the outlet heater hose (2).
12. Install the outlet heater hose clamp using the «J 39529»(ref-478473-S06617945892012061100000) .
13. Install the intake manifold tube. Refer to «Intake Manifold Tube Replacement»(ref-478531-S22201583172012061100000) .
14. Install oil fill tube.
15. Install the upper radiator baffle.
16. Install the battery. Refer to «Battery Replacement (Primary)»(ref-478456-S12007866262012061100000) .
17. Install the charged air cooler pipe. Refer to «Charge Air Cooler Inlet Pipe Replacement»(ref-478507-S12678002132012061100000) .
18. Install the surge tank assembly. Refer to «Radiator Surge Tank Replacement»(ref-478473-S18271161932012061100000) .
19. Install the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(ref-478507-S17677791602012061100000) .
20. Install the upper radiator baffle.
21. Inspect the automatic transmission fluid level. Refer to «Approximate Fluid Capacities»(ref-478438-S27013746372012061100000) .
22. Inspect the engine oil level. Refer to «Approximate Fluid Capacities»(ref-478438-S27013746372012061100000) .

1. Drain the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
2. Disconnect the heater cord from the coolant heater (4).
3. Loosen the coolant heater bolt.
4. Remove the coolant heater from the engine block.
5. Do not score the machined surface of the hole.
6. Grasp the plug with pliers.
7. Pull the plug from the engine block.
8. Clean the core plug hole in order to remove the following substances: Burrs Compound Paint Rough spots

1. Coat the O-ring seal and the cleaned surface of the plug opening with water resistant high-temperature grease lubricant GM P/N 9985164 (Canadian P/N 10953480), or the equivalent.
2. Tightly push the coolant heater (1) into the engine block.
3. Tighten the coolant heater bolt until both of the locking wings draw tightly against the inner wall of the engine block and tighten to 2 N.m (18 lb in).
4. Connect the heater cord to the coolant heater (4).
5. Fill the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
6. Inspect the cooling system for leaks.

1. Drain the cooling system/engine block. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
2. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-478431-S02322330072012061100000) .
3. For vehicles with regular production option (RPO) L76 (6.0L), perform the following steps. Otherwise, proceed to step 8.
4. Remove the oil cooler hose bracket bolt (1), if equipped.
5. Remove the oil cooler hose adapter bolts (2), if equipped.
6. Remove and discard the oil cooler hose adapter gasket, if equipped.
7. Position the oil cooler hose adapter end out of the way, if equipped.
8. Disconnect the coolant heater cord electrical connector (1).
9. Remove the coolant heater from the engine block.
10. Remove any burrs, sealer, or other rough spots.

1. If reusing the old coolant heater, apply thread sealant GM P/N 12346004 (Canadian P/N 10953480), or equivalent to the threads.
2. Install the coolant heater to the engine block and tighten to 50 N.m (37 lb ft).
3. Connect the coolant heater cord electrical connector (1).
4. For vehicles with RPO L76 (6.0L) perform the following steps otherwise proceed to step 10.
5. Position the oil cooler hose adapter end, if equipped.
6. Install a NEW oil cooler hose adapter gasket, if equipped.
7. Install the oil cooler hose adapter bolts (2), if equipped and tighten to 12 N.m (106 lb in).
8. Install the oil cooler hose bracket bolt (1), if equipped and tighten to 25 N.m (18 lb ft).
9. Lower the vehicle.
10. Fill the cooling system/engine block. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .

1. Drain the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
2. Raise and suitably support the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-478431-S02322330072012061100000) .
3. Disconnect the coolant heater electrical connector (2).
4. Remove the coolant heater from the engine block.
5. Remove any burrs, sealer, paint or other rough spots.

1. If re-using the old coolant heater, apply thread sealant GM P/N 12346004 (Canadian P/N 10953480), or equivalent to the threads.
2. Install the coolant heater to the engine block and tighten to 50 N.m (37 lb ft).
3. Connect the coolant heater electrical connector (2).
4. Lower the vehicle.
5. Fill the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .

1. Drain the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
2. Remove the right front tire and wheel. Refer to «Tire and Wheel Removal and Installation»(ref-478443-S27924613522012061100000) .
3. Disconnect the engine coolant heater cord.
4. Loosen the coolant heater bolt.
5. Remove the engine coolant heater from the engine block.
6. Do not score the machined surface of the hole.
7. Grasp the plug with pliers.
8. Pull the plug from the engine block.
9. Clean the core plug hole in order to remove the following substances: Burrs Compound Paint Rough spots

1. Coat the O-ring seal and the cleaned surface of the plug opening with water resistant high-temperature grease lubricant GM P/N 1052196 (Canadian P/N 5264008), or the equivalent.
2. Align the coolant heater element to point towards the top of the engine.
3. Tightly push the coolant heater into the engine block.
4. Tighten the bolt on the engine coolant heater until both of the locking wings draw tightly against the inner wall of the engine block and tighten to 2 N.m (18 lb in).
5. Connect the heater cord to the coolant heater.
6. Install the right front tire and wheel. Refer to «Tire and Wheel Removal and Installation»(ref-478443-S27924613522012061100000) .
7. Fill the cooling system. Refer to «Cooling System Draining and Filling (Static Fill)»(ref-478473-S36002101132012061100000) , «Cooling System Draining and Filling (Vac N Fill)»(ref-478473-S20462683752012061100000) , «Cooling System Draining and Filling (Static Fill Diesel)»(ref-478473-S09185496382012061100000) .
8. Inspect for coolant leaks.

1. Raise and suitably support the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-478431-S02322330072012061100000) .
2. Disconnect the coolant heater electrical connector (1).
3. Remove the coolant heater cord retainer (1).
4. Remove the coolant heater cord retainers (1).
5. Remove the coolant heater cord.

1. Install the coolant heater cord.
2. Install the coolant heater cord retainer (1).
3. Install the coolant heater cord retainers (1).
4. Connect the coolant heater electrical connector (1).
5. Lower the vehicle.

1. Raise and suitably support the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-478431-S02322330072012061100000) .
2. Disconnect the coolant heater electrical connector (1).
3. Remove the coolant heater cord retainers (1).
4. Remove the coolant heater cord.

1. Install the coolant heater cord.
2. Install the coolant heater cord retainers (1).
3. Connect the coolant heater electrical connector (1).
4. Lower the vehicle.

1. Raise and suitably support the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-478431-S02322330072012061100000) .
2. Disconnect the coolant heater electrical connector (1).
3. Remove the coolant heater cord retainer (1).
4. Remove the coolant heater cord retainer (1).
5. Remove the coolant heater cord retainer (1).
6. Remove the coolant heater cord.

1. Install the coolant heater cord.
2. Install the coolant heater cord retainer (1).
3. Install the coolant heater cord retainer (1).
4. Install the coolant heater cord retainer (1).
5. Connect the coolant heater electrical connector (1).
6. Lower the vehicle.