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 Additives for additional information.
Gasoline Octane
California FuelChevrolet Cobalt Service & Repair Manual. Vibration, Diagnosis
The designs and engineering requirements
of vehicles have undergone drastic changes over the last several years.
Vehicles are stiffer and provide more isolation from road input than they
did previously. The structures of today's stiffer vehicles are less susceptible
to man ...