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 get hot and no longer work well.

Vehicles can tow in D (Drive). Shift the transmission to a lower gear if the transmission shifts too often under heavy loads and/or hilly conditions.

The Tow/Haul Mode may be used if the transmission shifts too often.

See Tow/Haul Mode on page 9‑42.

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 on page 10‑23.

    See also:

    Roadside Assistance Program
    U.S.: 1-888-881-3302 TTY Users (U.S.): 1-888-889-2438 Canada: 1-800-268-6800 Mexico: 01-800-466-0801 As the owner of a new GMC, you are automatically enrolled in the Roadside Assistance program. ...

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    The vehicle has Electric Power Management (EPM) that estimates the battery's temperature and state of charge. It then adjusts the voltage for best performance and extended life of the battery. When t ...

    Rear Seats
    A. Seat Adjustment Handle B. Reclining Seatback Strap C. Sliding Seat Lever ...