Yukon/Denali XL 1500 4WD V8-6.0L VIN U (2004)
6. Remove the crankshaft sprocket.
7. Remove the crankshaft sprocket key, if required.
8. If required, clean and inspect the timing chain and sprockets. Refer to Timing Chain and Sprockets Cleaning and Inspection.
Installation Procedure
1. Install the key into the crankshaft keyway, if previously removed.