Originally Posted by phunk

Ya if you switch back and forth, you want to get the tank SUPER empty, as much as possible out. Its ok if there was like a half gallon of whatever left in the tank... but its not really convenient to drive around in circles waiting to burn off that last bit of fuel either. Switching here and there is OK... but changing fuel like your underwear wouldnt be recommended without flex fuel status, something we cannot do right now.