I have calculated the gas mileage on my truck many times and it always comes to 9 mpg. I never even use the 4x4 and still 9mpg. Is this normal? I know its a big engine but 9mpg? That just don't seem right.Another thing, what is the best kind of oil for my truck? Right now it has Motorcraft synthetic blend 10w30. Is there anything better that I should use or should I stick with Motorcraft? The truck has 179000 mi. on it and I change oil every 5000 mi.

 

i get 11.5 - 12 in the city with my truck and i'm pretty sure those number are wrong because i have the rear tank transfer to front pretty bag. my truck has 199,000

when was your last tune up?

 

Do you calculate it from gallons to fill the tank divided by the miles driven on that tank full? Do you have big tires that throw off your odometer? carry a lot of extra weight around, tools, etc.?........12 to 13 mpg would be pretty typical for your truck, 10w30 is correct oil for your truck.

 

As these guys have said, when was last tune up, how are you calculating, and have you made any mods that might affect fuel mileage? I find it hard to believe that a 95 is only getting 9 mpg unless you're moving a lot of loads all the time.

 

The last tune up was at 120000 and I used Bosch Premium Ignition Wires with Autolite Platinum spark plugs .The truck is completely original no modifications whatsoever. I never haul loads with it or use the 4x4. I calculate mileage by dividing the # of miles driven by the tank capacity.
(Ex. 180/19= 9.47)

 

That truck should easily get 12 mpg I would think. What trans does it have? Maybe replace the O2 sensor if it hasn't ever beenn done. A new fuel filter and air filter might help.

 

It should do a lot better than that. Does it have dual tanks? If so do both work? You may have the fuel transfer problem. Does it run rich or can you smell raw gas? Check fuel presure and for a leaky fuel pressure regulator(pull vacuum line off there should be no fuel leaking). Lastly pull codes by putting a jumper between STI and Sig-Rtn lines on the EEC test haress(drivers side inner fender), and turn the key to run.. codes will flash on the check engine light. Post up your results.

 

hell my buddy has a 96 5.8 4x4 an he gets roughly 14 or so around town......with 270k on the truck. and my 92 5.0 4x4 gets about 15 city 17-19 highway with 102k. thats hand calculated averages over the past year.

i'd say you need to check fuel pressure an pull codes like everyone else said.

heck i have a 75 IH shortbed 2wd pickup. with a 392 4bbl and a 4spd it gets 13 if i baby it........having fun i get about 7-8 at about 110.......and ih's can drink some fuel......so you should be easily getting 14 if you baby the truck

 

there's the problem. you should calculate by the miles driven and then the # of gallons it takes to fill the take up. i highly doubt that you run the tank all the way empty before filling up. say it takes 16 gallons to fil it up and you drive 180 then your getting 11.25.

 

yeah what squints said. I still can't believe an unmodded 5.8 4x4 gets 14 in town when my 5.0L barely gets 13

 

The truck has the E4OD trans and I changed the tranny fluid and filter about two months ago. I also changed the air and fuel filters and replaced the O2 sensor. I know that the tranny probably needs to be replaced but was told that it woul cost about 2k and I cant afford that. The truck does have dual tanks and they both work and have no leaks. I talked to a mechanic friend of mine and he said that even though I never use the 4x4, the Automatic hubs still make it use more gas and that I need to get manual locking hubs but I would also need a automatic/manual conversion kit that costs over $100 and the hubs would be about $130 and I can't afford that either. I lost my job last week so I cant afford to do anything now but I joined the NAVY yesterday but won't be shipping out til Sept 22 so i will be short on cash until then.

 

If the hubs are unlocked then they aren't costing you milage, easy to check too just jack up a corner and spin the wheel, if the drive axle does not spin too then the hub is unlocked as it should be and manual hubs will make no difference.

Do the checks I mentioned above and report your findings, shouldn't cost you anything to see if there is a problem that is affecting milage.

 

If it's been 60k since the last tune-up, it needs it again. You will see a lot of advice in here about avoiding platinum plugs, they can make the truck run funny and affect mileage. I would go with plain old copper autolites.

You are calculating the mileage wrong, and it's throwing your calculation way off. I'm surprised you didn't notice that when you fill the tank, it takes less than 19 gallons of gas.

You have to divide the miles driven by the *actual* amount of gas used, not by the tank's capacity.

 

hmmmm, my 460 gets 14.2 with wifey driving it
i get 8
lolol

 

I have a 95 f150 4x4 5.8 with the E40d transmission. And I get just about 10mpg. Just had everything tunned up a year ago. I thought for sure that it would at least get 12 to 14. I don't haul anything around. I mainly just use it to go to and from school and work. I dont think that anything is wrong with it but if there was what do you think the issue might be.