New for 2010

GM has dropped the long-running 6.0-liter V-8 engine from the Sierra lineup, leaving the powerful 6.2-liter V-8 for heavy towing needs. The rest of the Sierra's eight-cylinder lineup benefits from increased availability of its new six-speed transmission for regular and extended cab models equipped with the 5.3-liter V-8. Also, the 4.8-liter and 5.3-liter V-8 engines have been enhanced, with variable valve timing for improved emissions and better fuel economy.

Those with portable MP3 players can connect and play their music collections with the truck's audio system through a USB connection. Standard side curtain and side-impact airbags are welcome safety additions.

    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. ...

    Fuel E85 (85% Ethanol)
    Vehicles that have a FlexFuel badge and a yellow fuel cap can use either unleaded gasoline or ethanol fuel containing up to 85% ethanol (E85). See Fuel E85 (85% Ethanol) on page 9‑53. For al ...

    Manual Rearview Mirror
    Hold the inside rearview mirror in the center and move it for a clearer view behind the vehicle. Adjust the mirror to avoid glare from the headlamps behind you. Push the tab forward for daytime us ...