Driving on Grades
Reduce speed and shift to a lower gear before starting down a long or steep downgrade. If the transmission is not shifted down, the brakes might have to be used so much that they would get hot and no longer work well.
The vehicle can tow in D (Drive).
Use a lower gear if the transmission shifts too often.
When towing at high altitude on steep uphill grades, engine coolant boils at a lower temperature than at normal altitudes. If the engine is turned off immediately after towing at high altitude on steep uphill grades, the vehicle could show signs similar to engine overheating.
To avoid this, let the engine run while parked, preferably on level ground, with the transmission in P (Park) for a few minutes before turning the engine off. If the overheat warning comes on, see Engine Overheating.
See also:
Diagnostics
OnStar Vehicle Diagnostics will
perform a vehicle check every
month. It will check the engine,
transmission, antilock brakes, and
major vehicle systems. It also
checks the tire pressures, if ...
Rainsense™
For vehicles with Rainsense, a sensor located near the top center of the
windshield detects the amount of water on the windshield and automatically
controls the frequency of the windshield wiper.
...
General Towing Information
Only use towing equipment that has been designed for the vehicle.
Contact your dealer or trailering dealer for assistance with preparing the
vehicle for towing a trailer.
See the following trai ...






