Tom, I have a 6.0 L diesel in an 04 F250. 6 speed standard non automatic 4X4 I get 17 mpg running around town, 20 or 21 on the highway. 17 towing in flat land 13 or 14 towing in the mountains. This is at least 25% better than the old F150 with a gas engine bill 25 ft Trade Wind in WV