2000 Chevrolet Silverado 1500 Pickup Owner's Manual - Page 261

yellowblue When towing at high altitude on steep uphill grades, consider the following: Engine coolant will boil at a lower temperature than at normal altitudes. 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) (or the manual transmission out of gear and the parking brake applied) for a few minutes before turning the engine off. If you do get the overheat warning, see "Engine Overheating" in the Index. 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) yet for an automatic transmission, or into gear for a manual transmission. 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) for an automatic transmission, or REVERSE (R) for a manual transmission. 5. If you have a four-wheel-drive vehicle, be sure the transfer case is in a drive gear and not in NEUTRAL (N). 6. Release the regular brakes. 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. 4-65