2012 Chevrolet Avalanche Owner's Manual - Page 280

9-30 Driving and Operating { WARNING It can be dangerous to get out of the vehicle if the automatic transmission shift lever is not fully in P (Park) with the parking brake firmly set. The vehicle can roll. Do not leave the 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 the vehicle will not move, even when you are on fairly level ground, always set the parking brake and move the shift lever to P (Park). { WARNING If the vehicle has a four-wheel drive transfer case with a N (Neutral) position, and the transfer case is in N (Neutral), the vehicle may roll, even if the automatic transmission shift lever is in P (Park). So, be sure the transfer case is in a drive gear - not in N (Neutral). Always set the parking brake. Follow the proper steps to be sure the vehicle will not move. See Shifting Into Park on page 9‑26. If parking on a hill and pulling a trailer, see Driving Characteristics and Towing Tips on page 9‑63. Automatic Transmission The vehicle has a Hydra-Matic® 6L80 automatic transmission, and has an electronic shift position indicator within the instrument panel cluster. The electronic shift position indicator displays when the shift lever is moved out of P (Park). There are several different positions for the shift lever. See "Range Selection Mode" under Manual Mode on page 9‑33. P (Park): This position locks your rear wheels. It is the best position to use when you start the engine because the vehicle cannot move easily.