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Flywheel: Service and Repair




Engine Flywheel Replacement (LS9 and LSA)

Special Tools

* J 42386-A - Flywheel Holding Tool

* J 45059 - Angle Meter

Removal Procedure

Caution:
Failure to follow the proper removal and installation procedures may result in damage to the engine crankshaft thrust bearing.

Caution:
When tilting down the rear of the driveline, observe the clearance between the rear of the engine and the composite dash panel. Do not allow the engine to rest unsupported against the composite dash panel, or vehicle damage may result.

Caution:
When lowering and removing the rear of the driveline, observe the clearance between the rear of the transaxle assembly and the underbody to prevent damage.

Note:

* For manual transmission applications, note the position and direction of the engine flywheel before removal. The flywheel does not use a locating pin for alignment. Mark or scribe the end of the crankshaft and the flywheel before component removal. The engine flywheel must be reinstalled to the original position and direction. The engine flywheel will not initially seat against the crankshaft flange, but will be pulled onto the crankshaft by the engine flywheel bolts. This procedure requires a 3 stage tightening process.

* DO NOT remove the prop shaft hub or flex plate from the automatic transmission engine flywheel. The flywheel, prop shaft hub, and flex plate are balanced as an assembly. If service is required, the entire flywheel assembly should be replaced.




1. Remove the catalytic converters.

2. Remove the driveline support, if equipped with an automatic transmission. Refer to Driveline Support Assembly Replacement Driveline Support Assembly Replacement.

3. Remove the clutch assembly, if equipped with a manual transmission.

4. Mark or scribe the end of the crankshaft and the manual transmission flywheel. Refer to Engine Balancing Procedures.




5. If equipped with an automatic transmission, remove the engine flywheel bolts.




6. If equipped with a manual transmission, remove the engine flywheel bolts.

7. Remove the engine flywheel.

Installation Procedure

Note: For manual transmission applications, note the position and direction of the engine flywheel before removal. The flywheel does not use a locating pin for alignment. Mark or scribe the end of the crankshaft and the flywheel before component removal. The engine flywheel must be reinstalled to the original position and direction. The engine flywheel will not initially seat against the crankshaft flange, but will be pulled onto the crankshaft by the engine flywheel bolts. This procedure requires a 3 stage tightening process.

DO NOT remove the prop shaft hub or flex plate from the automatic transmission engine flywheel. The flywheel, prop shaft hub, and flex plate are balanced as an assembly. If service is required, the entire flywheel assembly should be replaced.




1. Install the flywheel (2) to the crankshaft.

2. Apply threadlock GM P/N 12345382 (Canadian P/N 10953489), or equivalent, to the threads of the flywheel bolts (1).





Caution: Refer to Fastener Caution Fastener Caution.

3. Install the J 42386-A - flywheel holding tool and bolts. Use one M10 - 1.5 x 120 mm and one M10 - 1.5 x 45 mm bolt for proper tool operation. Tighten the J 42386-A - flywheel holding tool bolts to 50 Nm (37 lb ft).




4. Install the engine flywheel bolts.

1. Tighten the engine flywheel bolts (1-9) a first pass in sequence to 20 Nm (15 lb ft).

2. Tighten the engine flywheel bolts (1-9) a second pass in sequence to 50 Nm (37 lb ft).

3. Tighten the engine flywheel bolts (1-9) a final pass in sequence to 100 Nm (74 lb ft) using the J 45059 - angle meter.

5. Install the driveline support, if equipped with an automatic transmission. Refer to Driveline Support Assembly Replacement Driveline Support Assembly Replacement.

6. Install the clutch assembly, if equipped with a manual transmission. Refer to Clutch Assembly Replacement (LS3/LS7) Service and RepairClutch Assembly Replacement (LS9) Service and Repair.

7. Install the catalytic converter.