Dennis Hinds

The Car Talk guys Click and Clack on NPR say that it is a joke for manufactures to tell you to use higher octane gas. They do admit that you will not get as good a gas mileage with just regular gas. That could account for your less range. I have been alternating between regular and middle grade gas for years because if I use all regular I can tell there is a slight hesitation in acceleration. The hardest part about that method is remembering what you last put in the tank.