have 2000 V10 Excursion 2WD and a 6800# boat(no fuel) and triple trailer(1500#?) boat has 217 gal gas tank.
Excursion with no boat and 80-85 mph gets 13.8-14.1 mpg

With boat at any speed from35-70mph it gets 5-7mpg. usually 6mpg. That is with it not in OverDrive and no cruise control. Is that the best way to tow. Otherwise it is always down-shifting. Would dual exhaust help? How about K.&N. Air Filter?
Chip?
I know we need a F250 2wd diesel..but until then..

my f250 v10 doesnt get as good as yours on the hwy, but it does get as bad towing.

I owned v10 Excursion and my mileage was exactly the same as your results. I towed triple axle 35 boat. Do not tow in O/D. Real hard on the transmission. The v10 has plenty of power just a little hard on gas towing. The money you will spend to save few bucks on gas may not be worth it. I went with a dually Powerstroke and it pulls 10 mpg towing and 14 non-towing. Wow I gained 4 mpg! If I amortize the cost of a diesel option ($5k) it may take me years.....to recover my cost. And now the cost of diesel fuel is more than premium gas. UGH..

I have a 4WD Excursion V-10 14mpg highway, 6-8 towing 37 Outerlimits. I have K&N filter, chip and dual exhaust

5.4 L super-crew F-150, 16 mpg not towing, 10mpg while towing 7K 288...

I'm getting 9-10 towing 11k 2 car trailer with my X. 12.5 -14.5 empty. It has 180.000 miles and gas mileage did increased after 100k.

I never worried too much about milage on my Ex(and people always ask at gas station) I've always said it's much better than my boat.
One thing interesting, last winter a friend commented about the snowmobiles using so much fuel, and correctly said we got better milage towing them with the ex, than driving all 3.

2000 V10 Ex, I average 12.3mpg and 6-8mpg with the boat

Chuck:

A K & N air filter and a Hypertech Programmer (chip) will improve performance and mpg. The Ford V10 is also a very thirsty engine. But, with diesel at .80 per gallon MORE than gas it's not so bad at this point.

Wannabe

Wannabe,
Can you run 87 octane with the chip? Where did you order your chip from? Thanks!