Sierra Classic 1500 2WD V8-4.8L (2007)
6. Rotate the crankshaft until the timing marks on the crankshaft and camshaft sprockets are aligned.
7. Remove the camshaft sprocket bolts.
8. Notice: Do not turn the crankshaft assembly after the timing chain has been removed in order to prevent damage to the piston assemblies or the
valves.
Remove the camshaft sprocket and reposition the timing chain.
9. Remove the camshaft retainer bolts and retainer.