2008 Chevrolet Tahoe Owner's Manual - Page 360

You may also want to activate the tow/haul mode if the transmission shifts too often. See "Tow/Haul Mode" earlier in this section for more information. When towing at high altitude on steep uphill grades, consider the following: Engine coolant at higher altitudes will boil at a lower temperature than at or near sea level. If you turn your engine off immediately after towing at high altitude on steep uphill grades, your vehicle may show signs similar to engine overheating. To 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 on page 5-31. 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 brake, but don't shift into PARK (P) yet. 2. Have someone place chocks under the trailer wheels. 3. When the wheel chocks are in place, release the regular brakes until the chocks absorb the load. 4. Reapply the regular brakes. Then apply your parking brake and shift into PARK (P). 5. If you have a four-wheel-drive vehicle, be sure the transfer case is in a drive gear and not in NEUTRAL. 6. Release the regular brakes. 4-60