Gasoline Specifications (U.S. and Canada Only)

At a minimum, gasoline should meet ASTM specification D 4814 in the United States or CAN/CGSB-3.5 or 3.511 in Canada. Some gasolines contain an octane-enhancing additive called methylcyclopentadienyl manganese tricarbonyl (MMT). We recommend against the use of gasolines containing MMT. See Fuel Additives on page 9‑75 for additional information.

    See also:

    Roadside Assistance Program
    As the owner of a new GMC, you are automatically enrolled in the Roadside Assistance program. See Roadside Assistance Program (U.S. and Canada) on page 13‑7 or Roadside Assistance Program (M ...

    If the Off Indicator is Lit for an Adult-Size Occupant
    If a person of adult-size is sitting in the right front passenger seat, but the off indicator is lit, it could be because that person is not sitting properly in the seat. If this happens, use the ...

    Compass Calibration
    The compass can be manually calibrated. Only calibrate the compass in a magnetically clean and safe location, such as an open parking lot, where driving the vehicle in circles is not a danger. It is ...