Notice: Perform TDC Offset Recovery procedure if the timing chain, timing gears, engine front cover, crankshaft position sensor, crankshaft or other components affecting the timing are replaced.

1. Disconnect both the battery negative cables from the batteries. Refer to Battery Replacement in Engine Electrical.
2. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
3. Remove the front grille and parking lamp assembly. Refer to Grille Replacement in Exterior Trim.
4. Remove the air conditioning condenser. Refer to Condenser Replacement in Heating, Ventilation, and Air Conditioning.
5. Remove the radiator from the vehicle. Refer to Radiator Replacement in Engine Cooling.
6. Remove the auxiliary engine oil cooler if equipped.
7. Remove the valve lifters from the engine block. Refer to Valve Lifter Replacement .
8. Remove the oil pump drive from the engine block.
9. Remove the timing chain from the engine block. Refer to Timing Chain and Sprocket Replacement .
10. Remove the camshaft thrust plate and spacer from the engine block.




Important: When removing the camshaft from the engine block, use caution as not to damage the camshaft bearing.

11. Remove the camshaft assembly from the engine block.

Important: When a new camshaft is being installed, use caution when installing the camshaft. Always install new valve lifters, engine oil and oil filter must be replacement at the same time.

1. Install the camshaft assembly to the engine block.

•	Coat the camshaft lobes with camshaft and valve Prelube GM P/N 1052365.

•	Lubricate the camshaft bearing journals with clean engine oil.




2. Install the camshaft thrust plate and the spacer to the engine block.

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.

3. Install the thrust plate retaining bolts.

Tighten
Tighten the bolts to 23 N·m (17 lb ft)

4. Install the timing chain and sprockets on the camshaft. Refer to Timing Chain and Sprocket Replacement .
5. Install the valve lifters in the engine block. Refer to Valve Lifter Replacement .
6. Install the oil pump drive in the engine block. Refer to Oil Pump Drive Replacement .
7. Install the radiator in the vehicle. Refer to Radiator Replacement in Engine Cooling.
8. Install the air conditioning condenser to the vehicle. Refer to Condenser Replacement in Heating, Ventilation, and Air Conditioning.
9. Install the auxiliary engine oil cooler if equipped.
10. Install the front grille and parking lamp assembly to the vehicle. Refer to Grille Replacement in Exterior Trim.
11. Refill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
12. Connect both the battery negative cables to the batteries. Refer to Battery Replacement in Engine Electrical.
13. Charge the air conditioning system. Refer to Refrigerant Recovery and Recharging in Heating, Ventilation, and Air Conditioning.
14. Perform TDC offset timing adjustment procedure. Refer to Fuel Injection Pump Top Dead Center Offset Adjustment in Engine Controls-6.5L-L65.