I just added an entry to my fuel log (but it's "old", from a little over a week ago). It was a tank with about half interstate and winding mountain roads, and the other half to and from work. I got a respectable 52.5mpg on the tank. Based on the readout from the MID, and it's relative accuracy, I am guessing the 64mpg tank cut out early, and my guess is it was actually closer to 55 or 56mpg, similar to what the MID was reading. So far this tank (to and from work only) I am averaging 56.0mpg according the the MID, looking forward to seeing how the tank turns out, but not so much looking forward to filling up
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