1997 GMC Sonoma Owner's Manual - Page 176

If you drive regularly in steepcountry, or if you're planning to visit there, here are some tips that can make your trips safer and more enjoyable. (See "Off-Road Driving" in the Index for information about driving off-road.) 0 Keep your vehicle in good shape. Check all fluid levels and also the brakes, tires, cooling system and transmission. These parts can work hard on mountain roads. Know how to go down hills. The most important thing to know is this: letyour engine dosome of the slowing down. Shift toa lower gear when you go down a steep or longhill. 0 Coasting downhill in NEUTRAL (N) or with the ignition off is dangerous. Your brakes will have to do all the work of slowing down. They could get so hot thatthey wouldn't work well. You would then il have poor braking or even none going down a hl. You could crash. Always have your engine running and yourvehicle in gear when you go downhill. 0 - Know how to go uphill. You may want to shift down to a lower gear. The lower gears help cool your engine and transmission, and you can climb the hill better. Stay in your own lane when driving on two-lane roads in hills or mountains. Don't swing wide or cut across the center of the road. Drive at speeds that let you stay in your own lane. 0 ~ If you don't shift down, your brakes could get so hot that they wouldn't work You would well. then have poor braking even none going or down a hill. You could crash. Shift down to let your engine assist your brakes on a steep downhill slope. 0 As you go over the top a hill, be alert. There could b of or something in your lane, like a stalled car an accident. 0 You may see highway signson mountains that warnof special problems. Examples are long grades, passing or no-passing zones, a falling rocks area winding or roads. Be alert to these and take appropriate action.