Diesel Trucks

I am sure didnt believe myself, I drive from southern cali up to Idaho to visit my parents and get that that mileage, my brothers 06 mega cab with a programmer gets 24-26mpg on the same trip. Trust me I was surprised. But have taken that trip many times, its 814 miles and I fill up twice, doing 75mph most of the way some places you have to slow down through towns.
You must have a freak with a weird tune or something. Like I said most guys are getting 16-18 with the modern engines. Hold on to that one.