As much as we seem to hate facts around here.. Flex fuel vehicles run on regular gasoline or
E85 
The
official MPG numbers as published by the Department of Energy/EPA actually show highway usage as 21mpg on gas, 16mpg on E85 for the 2012 Flex Fuel Suburban.
So if you figure it out for driving 100 highway miles as an example, you would use roughly 4.7 gallons of gasoline, or 6.25 gallons of E85 which contains
less than a gallon of gasoline.
Cheers,
Brad
