Shifting Into Four-Wheel Drive High or AUTO (Automatic Four-Wheel Drive)

GMC Sierra / GMC Sierra Owners Manuals / Driving and Operating / Drive Systems / Four-Wheel Drive / Shifting Into Four-Wheel Drive High or AUTO (Automatic Four-Wheel Drive)

Turn the knob to the Four-Wheel Drive High or AUTO position. This can be done at any speed, except when shifting from Four-Wheel Drive Low. The indicator light will flash while shifting. It will remain on when the shift is completed.

    See also:

    Under the Hood
    The Yukon Hybrid uses a two-mode hybrid system. The system augments the SUV's V-8 engine with two electric motors, both powered by a 300-volt battery pack. A cylinder-deactivation system cuts powe ...

    Footnotes — Maintenance Schedule Additional Required Services — Normal
    a) Check all fuel and vapor lines and hoses for proper hook-up, routing, and condition. Check that the purge valve, if the vehicle has one, works properly. Replace as needed. b) Or every four years, ...

    Filling the Tank
    If the vehicle has a diesel engine, see the Duramax diesel supplement for more information. WARNING Fuel vapor burns violently and a fuel fire can cause bad injuries. To help avoid injuries to you ...