GMC 2003 Safari Owner's Manual page 106

Shifting Into Park (P)
It can be dangerous to get out of your vehicle
if the shift lever is not fully in PARK (P) with
the parking brake firmly set. Your vehicle can
roll. If you have left the engine running, the
vehicle can move suddenly. You or others
could be injured. To be sure your vehicle won't
move, even when you're on fairly level ground,
use the steps that follow. If you're pulling a
trailer, see "Towing a Trailer" in the Index.
1. Hold the brake pedal down with your right foot and
set the parking brake.
2. Move the shift lever into PARK (P) like this:
0
Pull the lever toward you.
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