I'm still burning through the free fill up from the dealer but I have a fuel question. I've heard some saying the higher octane fuel will give you better mileage. My choices are 87,89,93 around here. It jumps about 30 cents a pop as you go up. Most of the fuel here also has about 10% ethanol. Will the higher octane pay for itself or be better on the engine etc. Would love to get your ideas and experiences with these trucks.