Okay, so I ( my parents ) have a '92 f150 with the 5.0 v8 and the e4od trans. We bought it from a relative for a good price and it's in good shape mechanically. I've filled it up with gas twice and one tank got 10.8 and the other 9.4 mpg. If I can't figure out a way to at least get it into the mid teens my parents are going to sell it. How can I fix this problem?

 

Start with a good tune up. Cap, rotor, plugs, wires, fuel filter, air filter. New properly gapped plugs will help a lot on an older vehicle.

 

You might want to start making plans...10-12 is about as good as it gets, especially if you like the pedal.

Even with a tune up and easy driving, 13-14 may be it.

You have to remember when this truck was new, gas mileage was not the end all for trucks that it is today.

Be glad you don't have the 5.8, I get 10-12 on the highway, and it is tuned up and in great shape.

 

I agree that you should either start making plans or practicing some *** kissing skills...

You can also check for vacuum leaks (the white vacuum line to the A/C blend door near the firewall on the passenger door is a common culprit and easy to replace).

Also could try Seafoming the engine.

Make sure that you are running at least relatively new copper core plugs

 

Alternatively, you could tell them that the amount of energy required to make the steel and components for a new car would be far greater than the extra fuel that you will burn in that truck compared to something with better mileage. Have you ever watched the steel forging process??? Sooooooooooooooooo much heat is required.....

 

Yeah I get about 13 with mine on a manual transmission and it has had everything tuned up/all fluids changed in the last year.

If you are willing to sink a couple hundred bucks into it and a little bit of time you can probably pull a few more mpg out of it. But to expect more than 12-13 is unrealistic.

 

Read up on the e-fan swap. From what I have read, it's good for a few MPGs

 

Maybe just try to alter your driving habits - don't accelerate too fast, don't slam on the brakes right before coming to a stop, try not to go over 60 mph. The truck was manufactured to get the greatest fuel economy at around 55 mph because that's the speed they test it at to determine fuel economy so if you are going over that then your gas mileage is dropping drastically. I understand in some states the speed limit is higher than 55 on the interstate and all that but try to keep it in that range on the highway and if you have cruise control it will help out as well. I've heard of some using a bottle of Lucas fuel treatment and getting a couple extra miles to the gallon

 

Start out slow, anticipate stops i.e. lots of coasting, never drive it over 60 mph. Never let it idle more than you have to. Start it and go. Make sure your tires are over inflated by at least 3-5 lbs and you have a good alignment. Take all extra weight out of the truck. If you have AC, don't use it and keep the windows closed while on the freeway. Google hyper-miling and see what else you can do. Otherwise, sell it and get something that gets better mpg.

I had a '96 F 150 with the 5.0L and E4OD. The best I could get was 14-15 mpg.