2002 Chevrolet Silverado 1500 Pickup Owner's Manual - Page 108

PARK (P): This position locks your rear wheels. It's the best position to use when you start your engine because your vehicle can't move easily. If your vehicle is equipped with the AllisonR Transmission, use park for stationary operation of the Power Takeoff (PTO) (if equipped). CAUTION: (Continued) If you have four-wheel drive, your vehicle will be free to roll -- even if your shift lever is in PARK (P) -- if your transfer case is in NEUTRAL. So, be sure the transfer case is in a drive gear, two-wheel high (2H) or four-wheel high (4H) or four-wheel low (4L) -- not in NEUTRAL. See "Shifting Into PARK (P)" in the Index. See "Shifting Into PARK (P)" in the Index. If you're pulling a trailer, see "Towing a Trailer" in the Index. CAUTION: It is 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. Don't leave your vehicle when the engine is running unless you have to. 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, always set your parking brake and move the shift lever to PARK (P). CAUTION: (Continued) 2-28