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 9‑41 for additional information.

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    Services Not Included in Roadside Assistance
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    Auxiliary Devices
    The vehicle may have a 3.5mm (1/8 in) auxiliary input jack located on the lower right side of the faceplate and for vehicles with a USB port, it is located in the instrument panel storage area. ...

    Diagnostics
    OnStar Vehicle Diagnostics will perform a vehicle check every month. It will check the engine, transmission, antilock brakes, and major vehicle systems. It also checks the tire pressures, if the vehic ...