2005 GMC Safari Owner's Manual - Page 198

If You Do Decide To Pull A Trailer If you do, here are some important points: Tow/Haul Mode Tow/haul is designed to assist while your vehicle is pulling a large or heavy load or trailer. Tow/haul is most useful while pulling such a load in rolling terrain, in stop-and-go traffic, or when you need improved low-speed control, such as when parking. The purpose of the tow/haul mode is to: • There are many different laws, including speed limit restrictions, having to do with trailering. Make sure your rig will be legal, not only where you live but also where you'll be driving. A good source for this information can be state or provincial police. • Consider using a sway control. See "Hitches" later in this section. • Reduce the frequency and improve the predictability of transmission shifts, • Don't tow a trailer at all during the first 500 miles (800 km) your new vehicle is driven. Your engine, axle or other parts could be damaged. • provide the same solid shift feel when pulling a heavy load as when the vehicle is unloaded, and • improve control of vehicle speed while requiring less throttle pedal activity. Press the button on the end of the shift lever to turn tow/haul mode on and off. While activated, the indicator light on the instrument panel will be on. Tow/haul mode will turn off automatically when the ignition is turned off. See Tow/Haul Mode Light on page 3-37. Tow/haul is most effective when the vehicle and trailer combined weight is at least 75 percent of the vehicle's Gross Combined Weight Rating (GCWR). See "Weight of the Trailer" later in this section. Driving with tow/haul activated without a heavy load will cause reduced fuel economy and unpleasant engine and transmission driving characteristics, but will not cause damage. • Then, during the first 500 miles (800 km) that you tow a trailer, don't drive over 50 mph (80 km/h) and don't make starts at full throttle. This helps your engine and other parts of your vehicle wear in at the heavier loads. • See "Driving on Grades" later in this section for more information. Three important considerations have to do with weight: • the weight of the trailer • the weight of the trailer tongue • and the weight on your vehicle's tires 4-34