I just got a 2008 F250 with a 5.4 it has 55,000 and the gas mileage is really bad in the city, and I would like to see if anyone has a suggestion on how I could improve it. I have checked it and running about 8 mpg in the city,and Hwy is about 15-16 mpg. I tried to drive very easy and found there no difference. I do not know if there's a problem with the truck. I checked the oil to see if I could seem gas in it and no I do not I also checked the air filter. It is clean. I am have a empty truck the reason I got the truck is to pull my Travel Trailer. I did not expect the fuel mileage to be this low. Ed

 

you can find a link by googling 2010 f250 5.4 low fuel mileage.

 

I have the same problem with my '04. It also has the 5.4 in it. Mine has the standard 3.73 gears, 4x4, with the leveling kit. It sits pretty high. It has a fairly aggressive tire, slightly wider than stock. I get 12. Doesn't seem to matter if I'm in town or on highway. It is always about 12.

Just bought the SCT tuner for it. Helps with throttle response, but not much difference in mpg's. Will take any tips... if I can't get a reasonable 14, I might have to get a Government Motors....

 

I have been asking around. I have not had chance to do anythiny at the present time. I have been told exhaust, and cold air intake helps out. I was also considering going with a tuner, Edge, Bullydog, etc. I have some other things I need to take care of first before spending money on this. I hope by end of next year I can do this. I will post anything I do, and any results I get.