I have a friend with a 2008 F350 6.4L - no issues at all except very thirsty. He sees about 17L/100km = 13.8 miles per gallon. His 2003 6.0L was better than that but was problematic hence the trade.

 

hooked mine on 20 foot stock trailer, the computer was telling me 25l/100kms. I was driving at 100kms/hr. That's 9.41 miles to the gallon travailing at about 60miles per hour.

 

There is a guy around town and he's only seen 8mpg.

 

My parents have one an 08 F-350 6.4/automatic CC SRW 4x4 3.73's. Fuel milage sucks, but they could affoard a $50k truck, they can affoard to pay for the fuel it sucks down. We had it loaded up to 19,000 pounds total of truck/camper/boat/everything loaded in it. It got 10mpg on a 250mile trip. I only heard the engine fan come on once, that was up this step 2 mile hill (it was like 15% is my guess, looked way more step than the 6% grades you see on the highway around here). We were next to a lake when we were going up when the fan kicked on, and it sounded like a big block gasser powered boat just floored it, kinda weird, but it was the only time I heard it come on (though it was only for like 2 minutes).

They love it though, except the fuel milage. But once the warranty is up they have plans to chip it which I hear increases the milages a good bit.

 

That don't sound bad to me at all. I was hearing stories of worse milage that this. I get 11 with my 5er on back....9k lbs. but i got that free fuel so i could care less...

 

friend of mine has one talked to him at eagle truck pull and he tried a bullydog and he said about 5min later all hall broke out. Said the dealer knew right away that he had played with it when they plugged it in. I guess it ended up takin out a couple of sensors. Other than that he like's it. he's had 03, 05, and now an 08 all ford's and all of them was played with.

 

I have an 08 6.4L F250 3.73s and get around 18 to 19. I have not towed anything heavy yet.

 

Welcome, Skeeter.

That's awesome! Is that hand calculated mileage?

 

well thats what the computer tells me. I will do it by hand on this tank to see how close it is.

Thanks for the welcome.

 

Yeah let us know. We're always looking for first hand knowledge on these new motors.