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. See “Automatic Engine Grade Braking” within Tow/Haul Mode on page 9‑26.

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 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 transmission in P (Park) for a few minutes before turning the engine off. If the overheat warning comes on, see Engine Overheating on page 10‑18.

On a long uphill grade, shift down and reduce the vehicle speed to around 88 km/h (55 mph) to reduce the possibility of the engine and the transmission overheating.

    See also:

    Arming the System
    To arm the system, do one of the following: ○ Press on the RKE transmitter. ○ Lock the vehicle using the key in the driver door. The alarm automatically arms after about 30 seconds. Th ...

    Multi-Band Antenna
    The multi-band antenna is located on the roof of the vehicle. This type of antenna is used with the AM/FM radio, as well as OnStar and the XM Satellite Radio Service System, if the vehicle has these f ...

    Brake System Messages
    SERVICE BRAKE SYSTEM This message displays along with the brake system warning light if there is a problem with the brake system. See Brake System Warning Light on page 5‑27. If this message ap ...