Tools Required

Caution: Before servicing any electrical component, the ignition and start switch must be in the OFF or LOCK position and all electrical loads must be OFF, unless instructed otherwise in these procedures. If a tool or equipment could easily come in contact with a live exposed electrical terminal, also disconnect the negative battery cable. Failure to follow these precautions may cause personal injury and/or damage to the vehicle or its components.

1. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
2. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
3. Drain the engine oil. Refer to Engine Oil and Oil Filter Replacement .
4. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
5. Lower the vehicle.
6. Loosen the water pump pulley bolts.
7. Remove the drive belt tensioner. Refer to Drive Belt Tensioner Replacement .
8. Remove the water pump pulley.
9. Remove the radiator outlet hose. Refer to Radiator Outlet Hose Replacement in Engine Cooling.
10. Remove the crankshaft balancer. Refer to Crankshaft Balancer Replacement .

Important: Be careful not to damage the crankshaft.

11. Pry out the crankshaft front oil seal with a flat bladed tool such as a large screwdriver. Use care to avoid damaging the crankshaft front oil seal bore or the crankshaft front oil seal contact surfaces.
12. Disconnect the electrical connectors from the following:

•	The camshaft position (CMP) sensor

•	The crankshaft position (CKP) sensor

•	The oil pressor sensor




13. Remove the crankshaft position sensor shield.
14. Lower the vehicle.
15. Install the engine support fixture. Refer to Engine Support Fixture .
16. Raise the vehicle.




Important: The oil pan can be dropped slightly for engine front cover clearance if all pan bolts are loosened and the oil level sensor is removed.

17. Remove the engine mount bracket for oil pan access. Refer to Engine Mount and Bracket Replacement .
18. Remove the oil filter.
19. Disconnect the oil level sensor electrical connector.
20. Remove the oil level sensor.
21. Remove the oil pan-to-engine front cover bolts.
22. Lower the oil pan and remove the oil pan-to-engine front cover bolts.
23. Loosen the remaining oil pan bolts to gain access for the engine front cover removal. DO NOT remove the remaining oil pan bolts.



24. Remove the crankshaft position sensor.



25. Remove the engine front cover bolts.
26. Remove the engine front cover with the oil filter adapter as one assembly.



27. Remove the engine front cover gasket.



28. If replacing the engine front cover, remove the oil filter adapter and pressure relief valve from the engine front cover.



29. If replacing the engine front cover, remove the water pump from the engine front cover.



30. If replacing the engine front cover, remove the oil pump cover and gear set from the engine front cover. Refer to Oil Pump Cover and Gear Set Replacement .
31. Inspect the oil pump cover and gear set. Refer to Oil Pump Cleaning and Inspection in engine Mechanical - 3.8L Unit Repair.



32. If replacing the engine front cover, remove the camshaft position sensor from the engine front cover.
33. Inspect the timing chain for overall in and out movement. Maximum movement is 25.4 mm (1 in). Refer to Camshaft Timing Chain and Sprocket Cleaning and Inspection in Engine Mechanical - 3.8L Unit Repair.
34. Inspect the sprockets for wear.
35. Inspect the oil pan gasket. Replace the oil pan gasket if necessary.
36. Clean the engine front cover mating surfaces.

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

1. If replacing the engine front cover, install the camshaft position sensor to the engine front cover.

Tighten
Tighten the camshaft position sensor bolts to 10 N·m (89 lb in).




2. If replacing the engine front cover, install the oil pump cover and gear set to the engine front cover. Refer to Oil Pump Cover and Gear Set Replacement .



3. If replacing the engine front cover, install the water pump gasket and the water pump to the front cover.
4. Install the water pump bolts to the water pump.

Tighten

•	Tighten the long water pump bolts to 34 N·m (25 lb ft).

•	Tighten the short water pump bolts to 22 N·m (16 lb ft).




5. If replacing the engine front cover, install the pressure relief valve, the oil filter adapter gasket and the oil filter adapter to the front cover.
6. Install the oil filter adapter bolts to the oil filter adapter.

Tighten
Tighten the oil filter adapter bolts to 30 N·m (22 lb ft).




7. Install the new engine front cover gasket. Ensure that the sealing surfaces are not damaged.
8. Apply sealer GM P/N 1052080 or equivalent to the bolt threads.



9. Align the cogs on the crankshaft sprocket with the cogs on the oil pump gear set in the engine front cover.
10. Install the engine front cover to the engine.



11. Install the engine front cover bolts (1-7).

Tighten
Tighten the engine front cover bolts to 34 N·m (25 lb ft).




12. Install the crankshaft position sensor.
13. Install the crankshaft position sensor studs to the engine front cover.

Tighten
Tighten the crankshaft position sensor studs to 30 N·m (22 lb ft).




14. Install the new engine front cover seal using J 35354 .
15. Tighten the bolt until the crankshaft front oil seal is seated in the engine front cover.
16. Remove the J 35354 .
17. Install the oil pan-to-engine front cover bolts.

Tighten
Tighten the oil pan bolts to 14 N·m (125 lb in).

18. Install the oil level sensor

Tighten
Tighten the oil level sensor to 20 N·m (15 lb ft).

19. Connect the oil level sensor electrical connector.
20. Install the engine mount bracket. Refer to Engine Mount and Bracket Replacement .



21. Install the oil filter.



22. Install the crankshaft position sensor shield.
23. Connect the electrical connectors to the following:

•	The oil pressure sensor

•	The crankshaft position (CKP) sensor

•	The camshaft position (CMP) sensor

24. Install the crankshaft balancer. Refer to Crankshaft Balancer Replacement .
25. Lower the vehicle.
26. Remove the engine support fixture.
27. Install the radiator outlet hose to the water pump. Refer to Radiator Outlet Hose Replacement in Engine Cooling.
28. Install the water pump pulley.
29. Install the water pump pulley bolts.

Tighten
Tighten the water pump pulley bolts to 13 N·m (116 lb in).

30. Install the drive belt tensioner. Refer to Drive Belt Tensioner Replacement .
31. Fill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
32. Fill the crankcase with engine oil. Refer to Engine Oil and Oil Filter Replacement .
33. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
34. Inspect for leaks.
35. Perform the CKP system variation learn procedure. Refer to Crankshaft Position System Variation Learn in Engine Controls - 3.8L.