2007 GMC Acadia Owner's Manual - Page 380

Driving on Grades Your vehicle is designed primarily as a passenger and load carrying vehicle. If you tow a trailer, your vehicle will require more frequent maintenance due to the additional load. Because of the added load of the trailer, your vehicle's engine may overheat on hot days, when going up a long or steep grade with a trailer. If the engine coolant temperature gage indicates overheating, turn off the air conditioning to reduce engine load, pull off the road and stop in a safe spot. Reduce speed and shift to a lower gear before you start down a long or steep downgrade. 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 55 mph (88 km/h) to reduce the possibility of the engine and the transmission overheating. Parking on Hills {CAUTION: You really should not park your vehicle, with a trailer attached, on a hill. If something goes wrong, your rig could start to move. People can be injured, and both your vehicle and the trailer can be damaged. But if you ever have to park your rig on a hill, here's how to do it: 1. Apply your regular brakes, but don't shift into PARK (P). When parking uphill, turn your wheels away from the curb. When parking downhill, turn your wheels into the curb. 2. Have someone place chocks behind the trailer wheels. 380