There's a lot of things that impact mileage and I'm not sure you can easily compare MPG, especially in winter -
- D1 is blended with D2 in winter in varying percentages based on the temps being experienced in that particular area. The blend will be different in Minn then in Tennessee, for example. And no blending in Florida, except for MAYBE the panhandle. D1 has less BTUs, therefore yields less mpg.
- If you drive south to Florida you will be dropping in elevation. You may say that you don't notice it but my experience has been that I get better mpg going south to Florida as opposed to driving back north.
- The wind. Pulling a 5er into a headwind makes for less mpg. I know this is obvious, but it seems lake any amount of headwind affects my mpg.
Tim