Don't forget the half gallon or so of diesel used up every time your vehicle does a regeneration. All three of manufactures are working to cut down weight and improve aerodynamics to help mileage but personally, I don't see any improvement. I know that my mileage will improve once I retire and have more time to travel (read 60-65 mph) but for now we need to get there sooner so the right foot tends to be a little heavier
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