Yukon/Denali XL 1500 2WD V8-6.0L VIN U (2005)
7. Remove the crankshaft sprocket key, if required.
8. If required, clean and inspect the timing chain and sprockets.
Installation Procedure
1. Install the key into the crankshaft keyway, if previously removed.
2. Tap the key (1) into the keyway until both ends of the key bottom onto the crankshaft.
3. Install the crankshaft sprocket onto the front of the crankshaft. Align the crankshaft key with the crankshaft sprocket keyway.