Tools Required

Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

1. Disconnect the negative battery cable.
2. Remove the intake air resonator. Refer to Intake Air Resonator Replacement in Engine Controls.
3. Remove the intake plenum. Refer to Intake Plenum Replacement .
4. Remove the timing belt cover. Refer to Timing Belt Cover Replacement .



5. Remove the crankshaft balancer bolts.
6. Remove the crankshaft balancer.
7. Remove the timing belt. Refer to Timing Belt Replacement .
8. Counterhold the crankshaft gear with J 42065 and remove the crankshaft gear bolt with J 42098 .

The crankshaft gear bolt is tightened to a high torque specification, it may be necessary to use a large breaker bar with J 42065 and J 42098 .

9. Discard the crankshaft gear bolt.
10. Remove the crankshaft gear and collar.




Important: Use caution when drilling the pilot hole so as not to damage the area around and behind the seal.

11. Carefully drill a small, shallow, pilot hole into the steel ring of the seal.
12. Screw in a self-tapping screw.
13. Use pliers to pull out the front main oil seal.
14. Clean all the sealing surfaces.

1. Coat the lip of the front main oil seal with a small amount of GM P/N 12377985 chassis grease or equivalent to aid in installation.
2. Tap the front main oil seal into place with J 35268-A .

Ensure the front main oil seal is fully and evenly seated.




3. Install the collar and the crankshaft gear.

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 a new crankshaft gear bolt.

Tighten
Counterhold the crankshaft gear with the J 42065 and tighten the crankshaft gear bolt with the J 42098 to 250 N·m (184 lb ft) on the first pass, an additional 45  degrees on the second pass and 15 degrees further on the third pass.

5. Install the timing belt. Refer to Timing Belt Replacement .



6. Install the crankshaft balancer.
7. Install the crankshaft balancer bolts.

Tighten
Tighten the crankshaft balancer bolts to 20 N·m (15 lb ft).

8. Install the timing belt cover. Refer to Timing Belt Cover Replacement .
9. Install the intake plenum. Refer to Intake Plenum Replacement .
10. Install the intake air resonator. Refer to Intake Air Resonator Replacement in Engine Controls.
11. Connect the negative battery cable.
12. Reprogram the applicable accessories. Refer to Reprogramming Accessories After Battery Disconnect in Engine Electrical.