How are you checking your MPG? On a recent trip to Frankenmuth, Michigan, I clocked 27.2 MPG going and 27 MPH coming back. I was elated. It took 24 gallons. But that did not sound right. 27 x 25 is 675 miles. But I drove only 570. If you divide 570 miles by 25 gallons you get 22.8. So I...