GMC 2001 Yukon XL Owner's Manual page 397

At Least Once a Year
Key Lock Cylinders Service
Lubricate the key lock cylinders with the lubricant
specified in Part D.
Body Lubrication Service
Lubricate all hood latch assembly, secondary latch,
pivots, spring anchor, release pawl, rear compartment
hinges, outer liftgate handle pivot points, rear door
detent link, roller mechanism, liftgate handle pivot
points, latch bolt, fuel door hinge, cargo door hinge,
locks and folding seat hardware. Part D tells you what
to use. More frequent lubrication may be required when
exposed to a corrosive environment.
Starter Switch Check
CAUTION:
When you are doing this check, the vehicle could
move suddenly. If it does, you or others could be
injured. Follow the steps below.
1. Before you start, be sure you have enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular
brake. See "Parking Brake" in the Index if necessary.
NOTE: Do not use the accelerator pedal, and be
ready to turn off the engine immediately if it starts.
3. Try to start the engine in each gear. The starter
should work only in PARK (P) or NEUTRAL (N).
If the starter works in any other position, your
vehicle needs service.
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