Improved mileaged?

[stevechie]

Hi would like to know those of you who have the 20008 F350 6.4L engine if your mileage has improved after its break in period. A buddy of mine has the 07 6.0L after 50, 000km his fuel mileage improved by 50%. We went on a trip and our mileag was exactly the same. A year later after his break in period we went on the exact same trip and I had to fill up twice and he didn't. Will I expect the same results with my 08?

 

[dsonyay]

My 08 F350 has improved quite a bit since new. It now has 40K miles and I'd say it's gone up about 10 to 12%. I have the 4.10 rear end and auto tranny. As long as I drive about 63 mph and less the mileage is great (17-18mpg). All around driving is getting about 16mpg at the moment. But my truck is nearly all hiway driving.

 

[mick1955]

No improvement in mine except for when I installed the tuner, but only have around 13,000 miles...

 

[johnkid]

im gettin 9.0 city i got an intake and 5inch dpf bak leveling kit with 35's with programmer off and this is after the pcm flash i got about 13k as well as mick1955 .....am i gonna see improvement it was getin 10.3 without programmer and with 11.8 but i havent put bak the programmer bak on since the flash due to programmer not recognizing the vehicle had to send it in for reflash cuz ford is really crackin down as Rolland says from RBP and mine was 1 of 3 trucks where the programmer wouldnt work on this happend 3 times i get it bak tomm i think im done with RBP and goin with Spartan

 

[Black06]

Hi would like to know those of you who have the 20008 F350 6.4L engine if your mileage has improved after its break in period. A buddy of mine has the 07 6.0L after 50, 000km his fuel mileage improved by 50%. We went on a trip and our mileag was exactly the same. A year later after his break in period we went on the exact same trip and I had to fill up twice and he didn't. Will I expect the same results with my 08?

I experienced an improvement in the fuel economy on my 2006 6.0L after approx. 15,000 miles where it improved from 15.5 mpg to 18.5 mpg very consistent on the highway. I kept the truck through 50,000 miles and didn't see an improvement any further.

I'm hoping the 6.4L will react the same; I'm currently at 10,300 miles and short of the tuner, haven't seen much improvement.