2003 GMC Sierra 1500 Pickup Owner's Manual - Page 314

Stalling on an Incline If your vehicle stalls when you're crossing an incline, be sure you (and your passengers) get out on the uphill side, even if the door there is harder to open. If you get out on the downhill side and the vehicle starts to roll over, you'll be right in its path. If you have to walk down the slope, stay out of the path the vehicle will take if it does roll over. Driving across an incline that's too steep will make your vehicle roll over. You could be seriously injured or killed. If you have any doubt about the steepnessof the incline, don't drive across it. Find another route instead. Q: What if I'm driving across an incline that's not too steep, but I hit some loose gravel and start to slide downhill. What should I do? A: If you feel your vehicle starting to slide sideways, turn downhill. This should help straighten out the vehicle and preventthe side slipping. However, a much better way to prevent this is to get out and "walk the course" so you know what the surface is like before you drive it. 4-33