Fuel Mileage Concern

[Rinierd]

I have a 2006 F250 with a 8" Lift and 38" Tires. The truck has 88k miles on it. I used to get between 12-15 mpg all the time. Now I am lucky to break 10 mph and am normally in the 9.5 range. This is with mostly city driving. I realize if I really baby it I can get the mileage back up to 10.5. Anyone have any ideas on what might be causing this drop in mileage. I live in Florida, havnt towed anything in the last several months. The truck has an air-raid cold air intake and custom Magnaflow ehasut. Also I have a tonneu cover. Just cant figure out what would cause the sudden loss of fuel mileage.

Is brake dragging a real problem? If so, whats the best way to check for it?

Thanks

[armyguy209]

Three things...

1. Did you already have the lift and tires when you were getting the 12-15mpg?

2. Are you going by the lie-o-meter on the dash or are you hand calculating it?

3. Have your driving habits changed in the last few months?

These could be why the decrease in mileage or possibly a mechanical issue.

[s8v4o]

Originally Posted by Rinierd

... I am lucky to break 10 mph and am normally in the 9.5 range.
Thanks

Man that's really slow! Just kidding. What ^ just said plus be sure to check tire pressures. In the winter months tire pressures drop quite a bit so might be worth looking into. I do agree that your mileage seems really low though.

[choupique108]

whens the last time you changed your fuel filter or cleaned your air filter?

[Rinierd]

Have cleaned the air filter in the last couple weeks. Will need to check the fuel filter. Fidrty fuel filter could lead to poor fuel mileage?? Never thought about that.

[Lubbockguy1979]

Fuel filters should be a 15k change out. 6.0's are pickey