2010 GMC Sierra 1500 Crew Cab Owner's Manual - Page 394

When driving over bumps, rocks, or other obstacles, the wheels can leave the ground. If this happens, even with one or two wheels, you cannot control the vehicle as well or at all. Because you will be on an unpaved surface, it is especially important to avoid sudden acceleration, sudden turns, or sudden braking. Off-roading requires a different kind of alertness from driving on paved roads and highways. There are no road signs, posted speed limits, or signal lights. Use good judgment about what is safe and what is not. Approaching a Hill When you approach a hill, decide if it is too steep to climb, descend, or cross. Steepness can be hard to judge. On a very small hill, for example, there may be a smooth, constant incline with only a small change in elevation where you can easily see all the way to the top. On a large hill, the incline may get steeper as you near the top, but you might not see this because the crest of the hill is hidden by bushes, grass, or shrubs. Consider this as you approach a hill: . Driving on Hills Off-road driving often takes you up, down, or across a hill. Driving safely on hills requires good judgment and an understanding of what the vehicle can and cannot do. There are some hills that simply cannot be driven, no matter how well built the vehicle... Is there a constant incline, or does the hill get sharply steeper in places? Is there good traction on the hillside, or will the surface cause tire slipping? Is there a straight path up or down the hill so you will not have to make turning maneuvers? Are there obstructions on the hill that can block your path, such as boulders, trees, logs, or ruts? What is beyond the hill? Is there a cliff, an embankment, a drop-off, a fence? Get out and walk the hill if you do not know. It is the smart way to find out. Is the hill simply too rough? Steep hills often have ruts, gullies, troughs, and exposed rocks because they are more susceptible to the effects of erosion. . { WARNING: Many hills are simply too steep for any vehicle. If you drive up them, you will stall. If you drive down them, you cannot control your speed. If you drive across them, you will roll over. You could be seriously injured or killed. If you have any doubt about the steepness, do not drive the hill. 5-18 . .