View Here : What Is Flex Fuel
FHS: Vehicle Fuel Gasoline E85 (FlexFuel Truck) i believe the code is LC9 in the glovebox That was the RPO code for the all aluminum 5.3 engine in the GMT-900 trucks 2007-2013.
Flex Fuel - E-85 Ethanol. The ability of the new 2011 Chevy Silverado to run on most forms of alternative fuels today is very useful. These fuels, including the E-85 Ethanol fuel, are found in most every state with the exceptions of Alaska, Connecticut, Maine, New Hampshire, Rhode Island and Vermont.