I just bought a 2001 F250 4x4 auto with the 5.4 gas engine. I have only filled it up a few times because it sits most of the time.
Anyway, shouldn't I get better than 7 mpg?

I have changed plugs and boots, new fuel filter, new air filter and pcv.
Did not help much. Still only getting 7.6 mpg.

It did set a code last week. It was output speed sensor.
I have no idea what that is.

Any ideas about the mileage?

Thanks

 

Do you idle and warm the truck up a lot? Do you run large tires or are you stock? In your truck I would expect the range to be 10-16mpg's. 7.xx sounds like towing mpgs.

 

I've got a 2006 F350 5.4l - mainly used as a plow now, but in the summer unloaded in 2wd under mainly just driving around town with a tuner in it I get maybe 10 mpg, so you're not too far off.

Have 3.73 axle. If you have a 4.1, that eould hurt your mileage a bit.

 

I had an 04 5.4L F250 CC 2wd auto that I put 206k miles on that got 13-14mpg empty. It had a 2" leveling kit and a slightly bigger tire when I upgraded to 18" wheels (stock 4wd tire size). I also had magnaflow performance exhaust and I ran amsoil through it, which helped me 1-2mpg's. Stock, I was getting 12mpg. 7mpg sounds awfully low to me even considering yours is 4wd.

 

Check to make sure of a few things.

Calipers aren't sticking or stuck and move freely

Make sure your hubs aren't locked in 4wd

How many miles are on the truck, and what configuration is it?

Lastly, look at the door tag under AXLE and see what code it says. If you have larger gears it will slightly effect mileage

 

Five months ago I bought a 2001 F250 regular cab 4wd, 5.4, auto, with a flat bed. I put four tool boxes on it, took out the passenger seat and filled the cab with tools, too. I get 14mpg with it. Seriously. I stay around 2000 rpm or less. Last week I bought a 06 F250, 4wd, 6-spd manual, and seem to be getting around 11.5 mpg after two tanks (725 miles, about 63 gallons).

 

I have V10 , manual 5speed ,with lift and 35" tires , and leave the hubs engaged always.
I get 14 regularly , all hiway driving as I live 30 miles from town.

 

I did check the tires today. The truck sticker says 235s. The tires are 265s. I will look again to find the axle code. I would love to get anything over 10 mpg.

 

I looked today and the axle code is C1

Anybody know what that means?

 

C1= 3.73 limited slip