We towed our 5th Wheel for the first time last weekend....and I have to say I'm excited that my 2002 F250 7.3 ltr. averaged a little over 20 mpg. pulling for 2 l/2 hours.  From what I've heard and read...that's pretty good diesel mileage!  And, we had 5 people traveling in the truck!    My DH was a happy camper!!

-- Edited by Melstar on Thursday 23rd of December 2010 12:48:54 AM

Melanie, Congratulations on putting together such a nice RV package to travel in. It looks like a very nice setup and I like the looks of your blog page. 20MPG towing is unbelievable.....best I've ever heard anyone get with any diesel truck is 17MPG, the average most RV'ers seem to get is around 15MPG. Enjoy your new RV setup.

Melanie, Is this what the onboard computer says, or measured mileage on fill up? Some computers are way off reality. Mine is about 1.5 miles optimistic. I couldn't come close to that if I carried the rig halfway. :) I get about 9-10 towing and 14-16 truck alone.

What Fred said. Only, my onboard computer is off by 1.3 mpg, negative. By measued mileage on numerous fillups, we average 11 to 11.4 while towing. If it is 20 while towing that 5er, you could sell that truck for enough to get a couple of Sport Chassis Freightliners, and have a bunch of money for the bank. :)

Wow, I love my truck too,but I'd love it more if I had anything close to that MPG. I have a 2010 F-250 DSL, with just over 11,000 miles. For the first 7000, it got 10.8 according to the computer,towing or not,made no difference.5500 of the first 7000  miles,were towing in 100 degree temps. Just the other day, on a 700 mile non-towing trip,with a recently installed tonneau cover in place, the computer says 14.3, which seems to jive with the amount of fuel added, upon return from the last leg. I'm told and hope that as the miles driven increases, the fuel economy will get better. I think the cover helps too.I love the truck, in any event, just hope it gets better. Have a great holiday.

Richard

Melstar, thats great I can get real close to that when I'm not towing, the best I done while towing is just a little over 13. I have an 01 2wd, let me know if you have any mod's to the 7.3, I want to do the same thing.  Richard, good luck I have heard that the newer models have more emission controls on them and can not come close to the older 7.3 MPG.
 
Flyone  

-- Edited by flyone on Thursday 23rd of December 2010 12:55:38 PM

Thats impressive mpg, Never owned a Truck that got over 12 mpg... We double tow and we averaged 8.5 mpg for 6,000 miles. However I do idle my truck. Lot of the miles were in the Colorado Rockies.

P.S.  But I do love my Truck.

-- Edited by Delaine and Lindy on Thursday 23rd of December 2010 06:27:15 PM

OK, now I'm going to have to figure the mileage at fill up. The mileage I was going with was the onboard computer thing. It has showed 21.8 to 21.6 not towing. It went down to 20.5 towing. It really seems awesome to me....so maybe it is a little on the optimistic side, Fred. I have been told that the 7.3 w/o all the emissions stuff gets a lot better mileage. I will take a fill up mileage....and get back to you! :)

We tow a 33 ft Cedar Creek 5th wheel with our 7.3 L F-250. We get 10-12 towing. And usually around 15-17 while not towing. Up hills , down hills , off a cliff , still the same !!!

Have you looked at putting a chip on your 350' and opening up the air intake . This should add another 4 miles to a gallon. I have also added octane to my diesel and this has also helped.