You do everything imaginable wrong and wonder why the mileage sucks.

Make sure your tires are inflated to the max and check the front brakes and make sure they are not dragging.

When your MPG loaded and unloaded are about the same, that is a dead giveaway that your are over-geared.

 

You do everything imaginable wrong and wonder why the mileage sucks.

ya gotta infer that i'm a complete moron becuz i'm askin? point was... doing everything wrong still got me 9+ mpg! i was satisfied with that. i understand, hense the way i posed the question.

As for the loaded vs. unloaded being over-geared; thanks for the susinct response. i knew it was detrimental, just not sure if all or most of the problem.

i was hoping for the 13.5 mpg i used to get in my '03 7.3 f350 4x4 in combo driving (living 35 miles from city then running around town when got there)). would be off the charts happy to see 17+ on the hiway, never have in any truck so agree driving attitude needs adjustment.

i did want to do the studs and sct etc. prior to sleeper install (for cab lift) but they came out with that dang 7 yr 200k warranty and i was sittin on a truck about to hit 36 mnths old with less than a thousand miles on it (ford leftover on ebay). with 6.0 prob.s (prolly good part fixed by the studs and egr-) and issues with turbos and sitting, fig'd had to jump on it. would love for this to just run like the f's. does pull better than i thot it would, flat.

i do think your airdam is in order, dave. what was yer source for the rubber? or?

thanks guys, just liten up on me man!oke:

:blah:sorry for that!

 

very disturbed as i am not gettin much better than 9 mpg. i got 9.25 pulling a 12k lb 5th wheel in the mtn.s with foot in it.

I gotta agree with Dave on this. 12K on a 450, an E-series at that, is not going to get very good mileage. And then add mountains, a heavy foot, and a 6.0L, I'd be extremely surprised if it stayed in OD even with a headwind, much less a good grade to climb. The only thing you didn't do wrong (from a MPG point of view) was use a diesel.

not doing much better, at all, empty in flat lands.

From all I hear, that's normal for a high geared truck/van.

didn't expect great mileage but sheeez!

What were you expecting? In the city I get 10-12, and that's with never being above 40mph. Highway, it's more like 17-20.
Dave does get like a bazilion MPG, but not when he tows.

anything to check out?

--Re-think your driving style. The engine doesn't have to run wide open to tow. Just enough to be able to spool the turbo in OD. I know you're a 6.oh-no, so a VGT makes finding that spot harder. For me, in my OBS, that means about 1800-2000 rpm I can build quite a bit of boost without down-shifting. You want to be at as low an RPM you can be and still create enough heat to make boost when you need it.
--Make sure the 4x4 isn't engaged. I don't know what hubs are on the truck, but make sure the aren't sticking locked.
--Swap gears to 3.55 or 3.73. Yes, you loose acceleration and the capability to fly up mountains, but you improve mpg.
--Get rid of 4x4. A 2wd truck is lighter and has less friction than a 4x4 axle.
--Make sure the trailer brakes aren't dragging.
--Make sure the truck brakes aren't dragging.
--Lower the van, put on super skinny tires, add an air dam, remove the mirrors and replace with tiny cameras, create a fairing to smooth the transition from the van to the trailer, lower the trailer, put super skinny tires on the trailer, add wheel covers to the truck and trailer, add a sloped back to the trailer, run the tires at MAX psi, put a manual transmission in for mbetter control of shifting, remove all external protuberances from the truck and trailer (handles, antennas, running boards), and always drive with a tailwind.

 

Might have the computer reflashed or get a SCT & studs + a EGR delete.

 

geez feel for ya. 25yrs. ago I had a E250 Quadravan 4x4 and could get 8MPG with a 460 gasser and 35" monster mudders + I was 20 years old, not a good combo for MPG

 

I got my conveyor belting from a local industrial rubber supply house. This stuff is hard to find, but it is flat-out the best because road debris won't hurt it.