This thread - 35.5 mpg- what a crock!! - got me to thinking about an episode on TRAINS I saw a few weeks ago, with the following statement. This is exact, as I took a pic of the screen when it appeared cause it blew my mind away. History channel, "MODERN MARVELS" - TRAINS Factors: 1 Stopping/starting 2 Differing friction for drive wheels 3 Operator's driving habits 4 Difference in efficiency of engines 5 Difference in efficiency of drive train (truck) and transmission lines to motors (train) I'm sure there are others, but these are all I could think of off-hand. I know virtually squat about trains, but it seems to me that the huge factors would be #'s 1 & 2 for the difference in efficiency, UNLESS there is a tremendous difference for # 5. IF #5 IS very significant, then this may be the answer to vehicular mileage, as the remainder would not change appreciably for the first 4 factors when considering the efficiency for "standard" vehicles. Any "scientific" thoughts? Incidentally, I had an '84 Cutlass Ciera (Olds) DIESEL that would get an average of 36-38MPG on the "I" at 70MPH. Loved it - except for the acceleration. Excellent torque in the mountains & you couldn't tell you weren't on level ground performance-wise.