Kinda strange..
 

I usually always use my front tank on the truck. The other day I switched to the rear tank and got 23 mpg for 3 days in a row. On the front tank I'd get about 12-15. Now, the back tank seems to be gettin a little worse cause yesterday I filled it up and only got 17 and today I got around 14. I'm driving the same as I always do so I know that's not the problem. Anyone have any ideas?
Thanks.

are you using the same gas station as normal? or same gas at all?
same route everyday?

edit: now that i think of it my truck gets better fuel mileage on the rear tank than the front too. so i also would like to know the problem and fix(if any).

Ya, same gas station, same route, same driving same everything. Kinda confusing me on why it was in the 20's and now it's droppin down again.

lol its one of them things where fords have a mind of their own just pet her and say good job and hope she keeps gettin good gas mileage lol i wish i could get near the 15mpg range

Believe me, it takes everything I can to get 15mpg. I drive WORSE than an old man. lol

Was the gas tank that you normally not using perhaps have old gas. Gas that was without Ethenol? maybe??

Gas with 10% Ethenol get about 10% worse fuel economy. 20-20% etc.

Ya, the gas was prolly about 5-6 months old. And I don't think there is Ethenol at the station I use.

Ummm.... if you are in the United Sates of America, you don't have a choice any more. Mr President Bush enacted a policy to help resolve gas supply and price issues and all gasoline now contains Enthenol blend.. probably between 10-20%.

The only exception is government and municipal emergency vehicles are allowed to run 100% gas because ethenol blends can also cause fuel vapor lock preventing vehicles from running when engine gets warm/hot.

I suspect that the front gas tank was pumping fuel into your rear tank when you switched the lever. Have you noticed that the front tank fuel is lower? There was a recall years ago (now outdated) that installed valves onto the fuel pumps. Revised fuel pumps have this valve built in. The switch turns off one pump and turns on the other pump. If the one-way valve is bad, the pumps will fill the opposing tank.

Bingo, it has nothin' to do with type of gas or the stars or how you drive, but that your rear tank return is putting fuel into your front tank with a lazy tank selector valve.

Adrianspeeder

I thought about that, but was hoping that the truck was just getting good gas mileage. :lol:

also is probably summer gas in the tank if its older.

but adrian is right on the money :thumbsup:

MTM Ford
You have a good looking truck, man

Thanks Alex, I like yours too. :rocker: I just recently put Clear Euro headlights on it and it made it look like a whole new truck. Gonna wait for a nice day and get a pic of it.