1997 GMC Suburban Owner's Manual - Page 234

Making Turns Driving On Grades Reduce speed and shift to a lower gear before you start down a long or steepdowngrade. If you don't shift down, you might have to use your brakes so much that they would get hot and no longer work well. On a long uphill grade, shift down and reduce your speed to around 45 mph (70 k d h ) to reduce the possibility of engine and transmission overheating. If you have an automatic transmission, you can tow in AUTOMATIC OVERDRIVE (GO). may want to You shift the transmission to THIRD (3) or, if necessary, a lower gear selection if the transmission shifts too often (e.&.,under heavy loads and/or hilly conditions). When towing at high altitude on steep uphill grades, consider the following: Engine coolant will boil at a lower temperature than at normal altitudes. If you turn your engine off immediately after towing at high altitude on steep uphill grades, your vehicle may show signs To similar to engine overheating. avoid this, let the engine run while parked (preferably on level ground) with the automatic transmission in PARK (P) for a few minutes before turning the engine off. If you do get the overheat warning, see "Engine Overheating" in the Index. NOTICE: Making very sharp turns while trailering could cause the trailer to come in contact with the vehicle. Your vehicle could be damaged. Avoid making verysharp turns while trailering. When you're turning witha trailer, make wider turns than normal. Do this so your trailer won't strike soft shoulders, curbs, road signs, treesor other objects. Avoid jerky or sudden maneuvers. Signal well in advance. Turn Signals When Towing a Trailer The arrowson your instrument panel will flash whenever you signal a turn or lane change. Properly hooked up, the trailer lamps will also flash, telling other drivers you're about to turn, change lanes or stop. When towing a trailer, the arrows on your instrument panel will flash forturns even if the bulbs on the trailer are burned out. Thus,you may think drivers behind you are seeing your signal when they are not. It's important to check occasionally to be sure the trailer bulbs are still working. 4-52