There's been plenty of discussion on this mpg on diesel truck forums.
As aerohead noted, there isn't nearly enough info to draw conclusions, much less anything useful. Safe to say that the Phoenix "test" was carefully staged to show maximum advantage. The advantage of urea seems obvious.
Early reports from commercial fleets show decent mileage, but let's remember that this type of vehicle has little to do with ordinary Americans. A bit like Corvettes: cool, but . . . .
Ford 6.7L diesel (yeah, the new one) - Bob Is The Oil Guy
(Use link provided for drivers comments about his run to Chicago)
The complexity of this motor is daunting, not just it's price: two separate cooling systems, for starters. FORD "tried" to make it that the cab does NOT need to be removed for service (unlike the previous generation).
(Let video play at least one minute. This an "ordinary" repair on this engine).
Cost of purchase, depreciation, repair, maintenance make this a potentially $70,000 vehicle with an unknown lifespan.
But, as to a half-ton being "unable" to tow a 10,000-lb trailer, that's incorrect. Weight is only one consideration, and not the most important in that determination. Trailer frontal area followed by aerodynamic resistance are more important; and trailer suspension also plays a real role in towing dynamics.
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