Engine Oil Additives/Engine Oil Flushes

Do not add anything to the oil.

The recommended oils with the dexos specification and displaying the dexos certification mark are all that is needed for good performance and engine protection.

Engine oil system flushes are not recommended and could cause engine damage not covered by the vehicle warranty.

    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. ...

    Service Publications Ordering Information
    Service Manuals Service Manuals have the diagnosis and repair information on the engines, transmission, axle, suspension, brakes, electrical, steering, body, etc. Service Bulletins Service Bulletin ...

    Federal Communications Commission (FCC) Rules and with Industry Canada Standards
    See Radio Frequency Statement on page 13‑21 for information regarding Part 15 of the Federal Communications Commission (FCC) Rules and with Industry Canada Standards RSS-GEN/210/220/310. ...