See also:

Overview
The GMC Sierra All Terrain HD concept is an exploration of heavy-duty truck capability combined with greater off-road versatility. It is highlighted by a bold exterior design, enhanced all-terrain ...

Engine Cooling When Trailer Towing
The cooling system may temporarily overheat during severe operating conditions. See Engine Overheating on page 10‑18. ...

Charging System Light
This light comes on briefly when the ignition key is turned to START, but the engine is not running, as a check to show it is working. If it does not, have the vehicle serviced by your dealer. The ...