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.
Vehicles with an automatic transmission can tow in D (Drive) but M (Manual Mode) is recommended. Shift the transmission to a lower gear if the transmission shifts too often under heavy loads and/or hilly conditions.
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 the engine is turned off immediately after towing at high altitude on steep uphill grades, the 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 P (Park) for a few minutes before turning the engine off. If the overheat warning comes on, see Engine Overheating .
See also:
How OnStar Service Works
Push this blue button to connect to a specially trained OnStar Advisor to verify your account information and to answer questions.
Push this red emergency button to get priority help from specially ...
Service Parts Identification Label
This label, located either in the glove box or the trunk area, has the following
information:
Vehicle Identification Number (VIN).
Model designation.
Paint information.
Production options ...
If Steam Is Coming From The Engine
Compartment
WARNING:
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine if you see or hear steam coming
from it. Turn it off and get everyone away ...
