Diesel Truck MPG

Camper 2012 wrote:

laknox wrote:
One thing that occurred to me a few weeks ago as I was filling up my wife's car and calc'ing her mileage. Almost all of us tend to over-fill our tanks; I know I do. Could that .5 to 1.5 gallons of "extra" fuel we pack in be why the dash lies to us when we hand-calc our mileage? I know DW's Genesis is consistently 1.2 to 1.5 mpg less than the dash reports but, as I say, I tend to pack the tank. Another issue that many may forget to take into account is the size of their tires. I'm running 265's instead of 245's on my D'max and I'm 4% under on both miles and speed. If I forget to add those miles when doing an mpg calc, I wonder why my mileage dropped. When I add them back in, I'm up to about where I expect to be.

Lyle

Thanks but I don't need 3500 for my 26' 5th wheel. I am looking for3/4 ton truck.

Just making a comment, Camper2012. I'll refer you back to my previous post, where I said that, from reading here, and other places, towing mpg seems to fall into about 9-12 mpg, no matter the size of your truck. Could be my '02 D'max 3/4 ton or the next guy's twin-screw Peterbuilt towing 20 tons. The single =biggest= factor in mileage is simply how fast you drive...to a point. All trucks seem to have a "sweet spot" where, all things being equal, they seem to just work better and more efficiently. One guy's spot might be 58 mph and the next guy, with the same model truck and a similar trailer, might be 62, or 64, or 66. I know I picked up about 1-1.5 mpg simply by slowing from 65 to 60. I just don't tow enough to get more accurate numbers.

Lyle