Thanks for sharing. And not surprising. 50% fuel consumption increase giver take when towing a big sail has been the recipe forever. Nothing new.
Old Dmax and Cummins were in the 18/9 category around 70-75 mph (flat no wind). Newer Cummins is in the 14/7 range thanks to the lift, tires and too tall gears. Would be the same 18/9 if it was stock.
It does lend some credibility to those who claim 25mpg out of their big diesels. But what they forget to mention is they’re drivin miss daisy and p!ssing off the line of cars behind them who may actually have some where to be before their next birthday.