[Guns Trucks & Beer]

Hey guys, I'm a newb here on ecomodder. I was dicussing economy with a friend and he referenced this site. Hopefully some of you guys may be able to help with my predicament....

I have a 2004 F250 Super Duty Supercab long bed FX4 off road package. It has a 5.4L in it an 4R100 automatic transmission.

This is my truck: it takes me to the hardest to reach of all fishing holes, pulls whatever trailer I need, takes me around with 16-25 inches of snow on the ground to pull my little lady out of the ditch. I have 305/70/16 10 ply tires because I need beefy tires for the trails and holding up this truck when I have 2 harleys in the bed and am pulling a trailer. I have a gooseneck for the fifth wheel, and yeah, I use it.

When I'm not using all of my trucks capabilities I have a tonneau cover. I drive moderately but I am not sacrificing my need to move to save gas (I'm sure some of you can relate).

What I want to do is find a way to make my truck get better fuel economy while cruising on the expressway. I currently average about 13.5mpg, and put on around 15-25K per year depending on if the harley is running or not.

I have been thinking about putting a blower on for more power (instead of getting a V10) and buying a gear vendors overdrive for my cross-MI adventures. Aside from that, anyone have any ideas how to improve economy?

But at the same time, here's what I am not willing to compromise to get improvements:

Tire size/ type. Off road tread and big tires are mandatory
Final gear ratio
Skid plates
ride height
Performance


I just really think there is a way to get all the way up to 15mpg average, I need to be resourceful. The steps I already have taken to getting better economy are as follows:

Cut out catalytic converter (picked up about 2mpg avg)
performance exhaust
iridium spark plugs
low restriction cold air intake
Good wax job
tonneau cover (picked up a about 1 mpg average)
never put on my cab visor :'(

Hope yall have some ideas on this big old truck! I need all the help I can get with 4wd season and the amount I drive!

Thanks in advance yall