1999 GMC Envoy Owner's Manual - Page 81

yellowblue Tow/Haul Selector Switch Your vehicle is equipped with a tow/haul selector switch. This switch is located on the shift knob. Four-Wheel Drive Because 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 two-wheel drive (2HI) for most normal driving conditions. NOTICE: You can use this feature to more efficiently tow or haul a heavy load. See "Tow/Haul Mode" in the Index for more information. Driving in the 4HI or 4LO positions for a long time on dry or wet pavement could shorten the life of your vehicle's drivetrain. 2-21