Well, Biggie, since you had to ask... I am trading up to an F250 SuperDuty XLT SuperCab, Turbo Diesel, 2WD (but w/Limited-Slip rear diff.) Long Bed. This is going to give me much better mileage, power, and interior space than my 95 F150. The Diesel gets roughly 20mpg (sometimes better) whether you are pulling something or not, highway or city. My F150 gets 15mpg if I am lucky (no trailer, little stop-and-go). I have to pull a horse trailer occasionally. An F350 is a little more expensive (roughly $1000) and I just do not forsee a need for the extra weight rating (or the extra weight).
BTW, while a personal 18-wheeler would be cool as heck... if I had the money, I would buy
THIS!!!. If you think you got that baddest @$$ SUV, lookout!
HAHAHAHAHAHA