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:

    Horn
    To sound the horn, press the center pad on the steering wheel. ...

    Storing XM Channels
    Drivers are encouraged to store XM channels while the vehicle is parked; see Defensive Driving on page 9‑3. Tune to stored radio stations using the presets, favorites button, and steering wheel ...

    Ignition Transmission Lock Check
    While parked, and with the parking brake set, try to turn the ignition to LOCK/OFF in each shift lever position. • The ignition should turn to LOCK/OFF only when the shift lever is in P (Park). †...