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:

    Customer Assistance Offices (U.S. and Canada)
    GMC encourages customers to call the toll-free number for assistance. However, if a customer wishes to write or e-mail GMC, the letter should be addressed to: United States GMC Customer Assistance ...

    Battery Power Protection
    This feature shuts off the dome and reading lamps, if they are left on for more than 10 minutes after the ignition is turned off. The cargo lamp shuts off after 20 minutes. This prevents the battery f ...

    File System and Naming
    The song name that displays is the song name contained in the ID3 tag. If the song name is not present in the ID3 tag, then the radio displays the file name without the extension (such as .mp3) as th ...