Tools Required

1. Remove the valve lifters. Refer to Valve Lifter Replacement .
2. Remove the charged air cooler. Refer to Charged Air Cooler Replacement .
3. Remove the air conditioning (A/C) condenser. Refer to Condenser Replacement in Heating, Ventilation, and Air Conditioning.
4. Remove the starter. Refer to Starter Motor Replacement in Engine Electrical.
5. Install J 44643 flush to the flywheel opening.
6. Remove the engine front cover. Refer to Engine Front Cover Replacement .



7. Remove the oil pump driven gear nut.
8. Remove the oil pump driven gear.




Important: The crankshaft reluctor and the oil pump drive gear are timed together at the factory. Do not remove the crankshaft reluctor from the oil pump drive gear.

9. Remove the oil pump drive gear and crankshaft reluctor.

•	Do not remove the crankshaft reluctor bolts.

•	Do not damage the reluctor teeth.




10. Using J 26900-12  (1) and J 26900-13  (2), measure the camshaft end play.

•	The production value is 0.050-0.114 mm (0.002-0.0045 in) and service limit is 0.20 mm (0.008 in).

•	Replace the camshaft gear or the camshaft thrust plate if measured value exceeds service limit.




11. Remove the camshaft reluctor screws.
12. Remove the camshaft reluctor.



13. In order to loosen the camshaft gear bolt use J 44643 in order to hold the engine from turning.
14. Loosen the camshaft gear bolt and leave the bolt finger tight.
15. Remove the camshaft thrust plate bolts through the holes in the camshaft gear.



16. Remove the camshaft with the camshaft gear attached.



17. Remove the camshaft gear bolt and discard.
18. Remove the camshaft gear.
19. Remove the camshaft thrust plate.
20. Clean and inspect the camshaft and bearings. Refer to Camshaft and Bearings Cleaning and Inspection .

If the camshaft bearings are worn or damaged the engine will require removal in order to replace the camshaft bearings. Refer to Engine Replacement .

1. Install the camshaft thrust plate to the camshaft.
2. Install the camshaft driven gear.
3. Install a NEW camshaft driven gear bolt.

Leave the bolt finger tight.




4. Install the camshaft into the cylinder block, align the camshaft gear to the crankshaft gear as shown.



5. Apply threadlock GM P/N 12345493 (Canadian P/N 10953488), or equivalent to the threads of the camshaft thrust plate bolts.

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.

6. Install the camshaft thrust plate bolts.

Tighten
Tighten the bolts to 22 N·m (16 lb ft).




7. Install the camshaft reluctor to the camshaft gear.
8. Install the camshaft reluctor bolts.

Tighten
Tighten the bolts in a cross-bolt pattern to 9 N·m (80 lb in) .




9. Reinstall J 44643 in the starter opening, if removed.
10. Install a NEW camshaft gear bolt.

Tighten
Tighten the bolt to 234 N·m (173 lb ft).




11. Using J 26900-12  (1) and J 26900-13  (2) measure the camshaft end play.

•	The production value is 0.050-0.114 mm (0.002-0.0045 in) and service limit is 0.20 mm (0.008 in).

•	Replace the camshaft gear or the camshaft thrust plate if measured value exceeds the service limit.





Important: Do not damage the teeth on the crankshaft reluctor.

12. Install the oil pump drive gear and reluctor to the crankshaft.



13. Install the oil pump driven gear.
14. Install the oil pump driven gear nut.

Tighten
Tighten the nut to 100 N·m (74 lb ft).

15. Install the engine front cover. Refer to Engine Front Cover Replacement .
16. Install the starter. Refer to Starter Motor Replacement in Engine Electrical.
17. Install the A/C condenser. Refer to Condenser Replacement in Heating, Ventilation, and Air Conditioning.
18. Install the charged air cooler. Refer to Charged Air Cooler Replacement .
19. Install the valve lifters. Refer to Valve Lifter Replacement .