I guarantee you will lose more than 3-4 mpg, my 07 F150 (5.4L) only got 9-10 mpg towing my 20' boat. Also, really think about how much you are going to use the boat. I love boating and grew up around boats, but Ohio weather sucks for us boaters most of the time. When I bought our new boat a couple years ago I had visions of getting everyone together and hanging out at the lake on weekends. Unfortunately it didn't happen that way, for some reason (unknown to myself) its hard to get a group together to go boating. What's wrong with people?? My wife says I'm an ass, I don't care about other people and my social skills need an overhaul, but its just that I don't deal well with stupidity and ignorance. Anyways, I now have a $34k boat that just sits in the driveway, it saw water 3 times last year and once (so far) this year. Anyone want to be my friend and go to the lake?