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 the battery negative cables from the batteries. Refer to Battery Cable in Engine Cooling.
2. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
3. Recover the A/C refrigerant from the A/C system. Refer to Refrigerant Recovery and Recharging in HVAC.
4. Remove the front grille and parking lamp assembly. Refer to Grille Replacement in Body Front End.
5. Remove the air conditioning condenser. Refer to Condenser Replacement in HVAC.
6. Remove the radiator from the vehicle. Refer to Radiator Replacement in Engine Cooling.
7. Remove the cylinder head assembly from the engine block. Refer to Cylinder Head Replacement .
8. Remove the oil pump drive from the engine block. Refer to Oil Pump Drive Replacement .
9. Remove the valve lifters from the engine block. Refer to Valve Lifter Replacement .
10. Remove the timing chain from the engine block. Refer to Timing Chain and Sprocket Replacement .
11. Remove the camshaft thrust plate and bolts from the engine block.



12. Remove the camshaft spacer from the engine block.

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




13. Remove the camshaft assembly from the engine block.
14. Replace the wood drift key if it is damaged.

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

Important: When installing the camshaft assembly into the engine block, use caution as not to damage the camshaft bearing during installation.

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 spacer to the camshaft.



3. Install the camshaft thrust plate 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.

4. Install the thrust plate retaining bolts.

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




5. Install the timing chain and sprockets to the camshaft. Refer to Timing Chain and Sprocket Replacement .
6. Install the valve lifters to the engine block. Refer to Valve Lifter Replacement .
7. Install the cylinder head assembly to the engine block. Refer to Cylinder Head Replacement .
8. Install the oil pump drive to the engine block. Refer to Oil Pump Drive Replacement .
9. Install the radiator to the vehicle. Refer to Radiator Replacement in Engine Cooling.
10. Install the air conditioning condenser in the vehicle. Refer to Condenser Replacement in HVAC.
11. Install the front grille and parking lamp assembly. Refer to Grille Replacement in Body Front End.
12. Refill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
13. Recharge the A/C system. Refer to Refrigerant Recovery and Recharging in HVAC.
14. Connect the battery negative cables to the batteries. Refer to Battery Cable in Engine Electrical.
15. Perform the TDC off set timing procedure. Refer to Fuel Injection Pump Top Dead Center Offset Adjustment in Engine Controls-6.5L.