I have and 04 F-350 with a 6.0 diesel. Currently I get about 12 mpg and doesn't change much from pulling 12K lbs or not. I'd like to try to get more mpg and would like to get everyones experiences and opinions.

intake, exhaust, chip, and properly inflated tires is about it

Im sure that all those would help. Do you have any real life examples? Cost is a concern. If i spend many thousands on upgrades and gain only a couple mpg it can take alot of fuel to payfor the upgrades. Upgrades don't make sence unless they can save $$$ in the long run.

I don't have a ford, im really suprised thats all your getting. the people I know with the fords are getting around 16. Do you have big rubber on it? is it 4 wheel drive? I went to dodge a few years ago, my 04 dually gets 18.5 to 19.5 around town. If it were my truck,I would put a flow through muffler on it, and a performance chip and that should help alot.

I have an 08 Chevy 2500 and am contemplating those upgrades but am nervous about the warranty nazis comming after me if their is a problem with something.

i had 2 f-350 srw 6.0 trucks something is not right with your truck.you should have you injectors and egr checked.i got 18 mpg empty on highway at 75mph ang 16 around twn in my 04 and about 1 mpg less in my 05 king ranch.if you do anything get exhuast and a sct programer. also check out www.thedieselgarage.com
scott
ps get a cummins and get 21-22mpg thats what i did

Something is wrong with your 6.0 if thats all your getting stock and unloaded, unless you live in a seriously hilly area with constant stop and go and on the gas hard.

If its a F-350 crew cab long bed dually, 4x4, with a bug deflector, a cap, and a windshield faring; that could easily cost 6 MPG...
...not to mention lift, tire size, axle ratio, and what might be in the bed on a daily basis.

WAY too many variables; which is why MPG numbers are all over the place on big trucks.

Switch all your fluids to synthetics. I and some friends also use AMSOIL 10w-40 High Performance Motor Oil, ATF and Gear Lubes along with their fuel additives and have typically picked up about 10% in fuel economy.

06 Ford F350 Dually 4x4 SWB with a 6.0 and WITH turbo back 4" exhaust, Airaid air box and an Edge/with Attitude programmer, synthetic fluids and a new egr valve, with Brentz Wheels and 34.5" tall Michelin 14 ply commercial tires still gets 12.3 mpg in town and as long as I keep rpms below 2000 on the highway I get 16 to 17 mpg, now with 12000 lbs of boat and trailer I get 11 mpg average,,,,the kicker is that the truck has 4:30 gears(it was part of the Tow Boss package from Ford) .