[InChiefsHeaven]

I had a friend tell me years ago that ethanol was way worse for gas mileage. I assumed it would not be because of the higher octane. As an experiment, I tried just regular unleaded, and like the OP noticed 3mpg immediately. i have not put ethanol in any of my vehicles since. It's 10 cents cheaper, but when I figured out the mileage variance, it's actually more expensive to run ethanol.

Now the same friend bought a new 2012 truck, and he says it's way better on ethanol than regular...so I guess the newer engines are designed for it? I dunno, but since a new vehicle is not in my future, it's regular gas for me...