Engine Flywheel Installation 6.2L LS3

Note: 

•	For manual transmission applications, note the position and direction of the engine flywheel before removal. Mark or scribe the end of the crankshaft and flywheel before component removal. The existing manual transmission engine flywheel must be installed to the original position and direction.

•	The flywheel does not use a locating pin for alignment and 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 propeller shaft hub or flex plate from the automatic transmission flex plate assembly. The flex plate and propeller shaft hub are balanced as an assembly. If service is required, the entire flex plate assembly should be replaced.

1. Install the automatic transmission flex plate to the crankshaft, if applicable.



2. Install the manual transmission flywheel to the crankshaft, if applicable. Refer to Engine Balancing.
3. Apply threadlock GM P/N 12345382 (Canadian P/N 10953489), or equivalent, to the threads of the bolts.

Caution: Refer to Fastener Caution in the Preface section.




4. Install the bolts.

4.1.	Tighten the bolts (1-6) a first pass in sequence to 20 N·m (15 lb ft).

4.2.	Tighten the bolts (1-6) a second pass in sequence to 50 N·m (37 lb ft).

4.3.	Tighten the bolts (1-6) a final pass in sequence to 100 N·m (74 lb ft).

Engine Flywheel Installation 6.2L LS9

Special Tools

For equivalent regional tools, refer to Special Tools

Note: 

•	Note the position and direction of the engine flywheel before removal. Mark or scribe the end of the crankshaft and flywheel before component removal. The existing engine flywheel must be installed to the original position and direction. Refer to Engine Balancing.

•	The flywheel does not use a locating pin for alignment and 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 step tightening process.

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 in the Preface section.




3. Install the J 42386-A tool and bolts. Use 1 M10 - 1.5 x 120 mm and 1 M10 - 1.5 x 45 mm bolt for proper tool operation.

Tighten the J 42386-A tool bolts to 50 N·m (37 lb ft).




4. Install the engine flywheel bolts.

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

4.2.	Tighten the engine flywheel bolts (1-9) a second pass in sequence to 30 N·m (20 lb ft).

4.3.	Tighten the engine flywheel bolts (1-9) a final pass in sequence to 40 degrees using the J 45059 meter .

Engine Flywheel Installation 7.0L

Special Tools

For equivalent regional tools, refer to Special Tools

Note: 

•	Note the position and direction of the engine flywheel before removal. Mark or scribe the end of the crankshaft and flywheel before component removal. The existing engine flywheel must be installed to the original position and direction. Refer to Engine Balancing.

•	The flywheel does not use a locating pin for alignment and will not initially seat against the crankshaft flange, but will be pulled onto the crankshaft by the engine flywheel bolts. This procedure requires a 2 stage tightening process.

•	When installing the friction washer to the rear face of the crankshaft, align the pilot hole of the crankshaft (1) and the locating hole of the washer (2).

1. Install the flywheel washer (132) to the rear face of the crankshaft.
2. Install the flywheel (134) to the crankshaft.
3. Apply threadlock GM P/N 12345382 (Canadian P/N 10953489), or equivalent, to the threads of the flywheel bolts (133).

Caution: Refer to Fastener Caution in the Preface section.




4. Install the J 42386-A holding tool and bolts. Use 1 M10 - 1.5 x 120 mm and 1 M10 - 1.5 x 45 mm bolt for proper tool operation. Tighten the J 42386-A holding tool bolts to 50 N·m (37 lb ft).



5. Install the engine flywheel bolts:

5.1.	Tighten the engine flywheel bolts (1-6) a first pass in sequence to 30 N·m (22 lb ft).

5.2.	Tighten the engine flywheel bolts (1-6) a final pass in sequence to 40 degrees using the J 45059 meter .