2005 GMC Envoy Owner's Manual - Page 101

SECOND (2): This position gives you more power but lower fuel economy than THIRD (3). You can use SECOND (2) on hills. It can help control your speed as you go down steep mountain roads, but then you would also want to use the brakes off and on. You can also use SECOND (2) for starting the vehicle from a stop on slippery road surfaces. FIRST (1): This position gives you even more power but lower fuel economy than SECOND (2). You can use it on very steep hills, or in deep snow or mud. If the selector lever is put in FIRST (1) while the vehicle is moving forward, the transmission will not shift into first gear until the vehicle is going slowly enough. Notice: Spinning the tires or holding the vehicle in one place on a hill using only the accelerator pedal may damage the transmission. If you are stuck, do not spin the tires. When stopping on a hill, use the brakes to hold the vehicle in place. Four-Wheel Drive If your vehicle has four-wheel drive, you can send your engine's driving power to all four wheels for extra traction. To get the most satisfaction out of four-wheel drive, you must be familiar with its operation. Read the part that follows before using four-wheel drive. You should use 2HI (two-wheel high) for most normal driving conditions. Notice: Driving on clean, dry pavement in four-wheel drive for an extended period of time may cause premature wear on your vehicle's powertrain. Do not drive on clean, dry pavement in four-wheel drive for extended periods of time. 2-27