I just bought a 2010 Ford F150 XLT 4.6L V8 last week. I topped off the tank on Monday afternoon and have driven 80 miles on this new tank and it has already used a quarter of the tank. This is a 36 gallon tank, and it was topped off. I expect about 15-16 MPG from everything I've read. My fuel gauge and MTE show a different story, and both are dropping significantly. I noticed this on the previous amount of gas that was in the truck when I bought it. It only has 52,000 miles on it, but would it need a tune up of some kind? I'm not the most knowledgeable in the car department, but could there be something that needs to be replaced already that would affect my gas mileage? I used Arco premium when I filled up, and what I've read on using Arco gas is 50-50. I don't know how it would affect a v8 though. I don't hit the pedal too hard, and I'm not towing/hauling anything currently. I only drive 18 miles round trip for work, so realistically I should be able to drive nearly the whole month on a full tank of gas. Any advice?

 

This was the problem with my mileage on my 2007 4.2 V6. It was stuck in one position and the engine was running rich. I was blowing black smoke out of the exhaust. http://www.partsgeek.com/catalog/2010/ford/f150/fuel_delivery/pressure_sensor.html
(The link is to 2010 part)

 

No CEL or codes, including any pending?

 

Everything looks good. The truck is in pristine condition. I'm going to test the mileage out a little more before I seriously look into anything to fix it. I'll monitor my driving habits and put quality gas into it and see if anything changes.

 

Define "quality gas"

 

Start with the easy things first. Check your tire pressure. Replace your air cleaner. Check your spark plugs. If you still aren't happy keep checking stuff.

BTW is your truck stock?

 

Also consider using a bottle of techrolene in your next tank of gas, it works better than STP or Lucas by far. 52K is enough to start clogging your injectors if poor quality gas has/is being used.


Also consider using regular in your truck unless you get pinging, or at least feel the computer backing off your timing (Loss of power). The different octane blends are made for different compression ratios/cylinder pressures. Too much octane and your vehicle may not run as well as it could with the lower octane. Only run as high of a grade as you need for it to run right.