Ford Powerstroke Diesel Forum banner

2008 F250

2K views 15 replies 8 participants last post by  chris2207 
#1 ·
I put a mini maxx, dpf/cat delete, s&b intake and exhaust on my truck a few weeks ago. Im not expecting to get great fuel mileage, but im only averaging between 10.5 and 11 mpg. That is about the same as what i was getting stock. I havent been running around town racing, just driving normal. Does anyone know what my problem could be??
 
#2 ·
I have a similar setup as you and have seen about a 25% increase in mileage. I have 3:73 gears and am using the shift schedule 1 Low strategy from H&S with the 250 tune. I recently changed to the 300 tune and am now seeing how that one does with the mileage.

Another thing I noticed is to check the tire size when loading your tunes to make sure the value there is correct for your vehicle.
 
#12 ·
I will say that I got real bad mileage on one leg of a 1500 mile trip due to bad diesel. I run the XRT pro using the mild 80 hp tune and the S1 low trans tune. I get almost 16 around town and 19 on trips. might want to try that set up and see what it does for you. Using the tuner you have of course. Just trying to think of how to help
 
#14 ·
did you hand calculate the mpg prior to tuning? i didn't and thought the computer was accurate, but it wasn't......the way i know for sure is that i get about 100-140 miles more per tank, with just city driving....i tuned my bosses truck the same as mine and he went to Seattle, 180 miles, on 1/4 tank
 
#15 ·
It may sound dumb but how are your fuel filters? Have they been changed recently? Also do you always fill up at the same fuel station? If so It might be worth switching stations to see if maybe the fuel is better somewhere else? It might be worth going back to stock and taking the truck in and have ford scan the motor. Because that fuel mileage is horrible. They might be able to find something that isnt correct and you can get it replaced under warranty. Also what are boost, EGTs, EBP, fuel pressure/rail pressure running? Might be able to see something through those numbers being really low/high? Maybe you have a boost leak you never knew about and that could be causing some issues? Im just throwing things out there.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top