I'm dissapointed--and or just breaking in?

[NutritionGuy1]

I recently purchased a 2008 6.4L F-350 2 wheel drive DRW auto tranny bone stock, truck to pull a 3 hrs aluminum horse trailer with a LQ(10,000-11000lbs loaded). Just got back from a trip from Oklahoma City to Des Moines on I-35. For the round-trip truck averaged 8.1 mpg--on the last tank on the way home it only got 6.9 mpg (all hand calculated). Running 72-75 mph with RPM's about 2250-2400.

Last year made the same trip with same trailer loaded the same way with a 2003 7.3L F-350 SRW 4X4 4r100-bone stock. Averaged 10 mpg.

Now I know that the 03 had 3.73 gears and I now have 4.10s--and I know that all this new EPA stuff hurts mileage--but is it supposed to be that low?

Also--on the last tank of fuel--it regenerated 3 times in 220 miles.

08 does only have 4200 miles on it--do I need to just have patience and let it break in more and how many miles will that take, is the EPA making no sense by reducing soot, but making me burn more diesel, or is something off with the truck.

Help--wish I had th 7.3L motor in this truck in some ways!

[compman72]

That looks normal to me for the economy. Regens - that might be normal for the time - they seem to be more frequent according to the driving habits & fuel.

[smotrs]

Yep, completely normal unfortunately.

[2x6 Bulldog]

The engine will continually break in until 10,000 miles. You might pick up 1 or 2 mpg more after complete break in. Try slowing down 5 or 10 miles per hour these trucks have a huge frontal area and the drag is huge. Thanks EPA and the government.

[guardrail22]

mine is nearing 40000 miles and I get 7.8-8.0 pulling a 37' 5th wheel.

Slow down to about 63-65. The truck has no aerodynamics at all.

Regens are using the fuel

[sawtooth]

I would watch your regens as that is hurting your mileage even more than normal. My truck has never regened 3 times in just over 200 miles. Actually mine normally regens every 400-1000 miles. I would watch this to see if it stays consistant.


For the guys that haul heavy all the time, how often do you regen?

[first_ford]

When I haul, the truck regens every 110-120 miles or every 2 hours I can't wait till I am comfortable with the warranty of the truck, and go with a tuner

[Captcaper]

Normal.

I have 36Know and 3.73 gears SRW F350 and it sucks fuel. 13.5 empty and 9mpg towing 3k enclosed trailer empty going from Ma. to NH interstate speeds of 70-75mph.

Truck runs very nice and rides well too. But I wish I had known about the MPG and fuel price increases coming back soon.

[sawtooth]

Well maybe it is normal then. I had always read that when you work the engine hard then heats are higher and you get more passive regens and less active ones. The crazy thing is my truck doenst seem to regen much at all even when i pull some lighter loads like 5-6K. I've only pulled 9K once but that was only for 100 miles. No regens though in that time period.

[DSTRBD]

The emissions garbage is the reason for poor mileage, plain and simple. It will get a little better with some more miles, but dont expect much.