Diesel or Gas

I had the the Ford F-250 Triton V-10 gas freaking hog, it new of only one standard of fuel mileage 8 miles to the gallon, towing it went down even more sometimes five miles to the gallon. Diesel are out their just keep look I found a 2004 dodge cummins 1 ton single axle 5 speed with only 89000 miles on it. Wow was I surprised ran a carfax and went to deal, they really wanted my truck and I wanted there's> I told them what I could do, no money exchanged hands a few dollars more in a monthly pay. It was what I could do. It pulls my 10000 pound trailer with ease. 68 miles an hour with cruise every where we travel and mileage increased to 12 to 14 towing not towing on highway 21!!!!! ya I'll never go back to a gasser!!!!