I have a 1974/75 Ford 250 Ranger XLT with a 390 Fe 4bbl and manual 4 on the floor. Everything stock including wheels and tire size. I live on a moderate hill and drive the truck as my daily driver to the firehall and back approx. 5 miles each way. I have two tanks but only use the rear one (19 gallons). I get around 100 miles (if that) and i am not pushing the pedal to the floor either. The engine revs are low and smooth, new oil, air filter etc. truck is well taken care of. Any ideas what i can do to improve the mileage? I mean 5.3 mpg on premium fuel 92 octane can't be right.

As always any suggestions/information is welcome.

cord

 

Hoist a sail?

I don't think these trucks were designed with fuel-efficiency in mind...

My mileage went down after I lost another valve seat...

I would suggest maybe tuning the carb a bit leaner and tweak the timing a bit - this is where a vacuum gauge comes in handy... I did that on my Fury and it seemed to help a bit with mileage...

 

74/75 not sure if you have a egr valve, but I had a 77 F150 4X4 351 and went from about 14 mpg to 4 mpg over night. I managed a self service gas station and had told a guy that ran the tune up shop next door about it and he took it over to his shop and tested it. Came back over and said the egr was bad and replaced it and the truck went right back to 14 mpg.

 

I'll second that. If you live in a state where you can get away with taking your EGR valve off, do it! I took the egr valve off a 400 that was giving me problems, set the carb right on top of the manifold and bolted it up, and it improved my gas mileage and performance astronomically. It could always be something else with the motor or carb but the EGR would be a good place to start.

 

Correct me if Im wrong, but wouldn't 92 Octane burn faster than 87 resulting in worse mileage?

 

Even with a FE in a 3/4 ton truck you should be pulling down at least 8mpg.

 

Absolutely no reason at all to removed the EGR valve if it is working properly. If it is not working right get a new one. You will be glad you did because one day I bet all states will start requiring all these old trucks to pass emissions again.

Everybody knows how much of a pain in the @ss it is to fix the emissions system on a truck that had the egr and vac lines and such hacked up by the previous owner.

 

I'm surprised that engine has high enough compression to need the 92, does it ping on the cheap stuff? Also, 5 miles isn't much, that's a lot of engine to warm up, could be the choke is never fully opening, or if it is, it's right where you shut down. Might be worth a look.
Pat D.

 

i agree with pat d. the trip is too short. if i drive 5 miles in my 91 with a 460, it uses almost the same amount of fuel as when i drive 25 highway miles. all of it is on the acceleration, or at least most of it, and not bein warm doesnt help.

 

How long has it been like this? Why don't you use the front tank - I had an '88 with dual tanks and it would fill the front tank with the unburned fuel when I ran off the rear tank - to the point that it started pouring out of the front tank's filler neck at a stoplight one day.

-Chris

 

thats a very good point torquemeister. you might have a front tank full of gas. lol.

 

These old truck aren't like the newer EFI trucks there is no return line so you can't fill one tank from the other.
-Johnboy

 

I third.. or whatever place im in, on the EGR valve if you have one. Pretty big drop though. Considered a fuel leak?

Maybe someones picking on you and syphoning your fuel out on a daily basis haha

 

There's no reason to use premium fuel in that engine. Use 87 octane; anything higher is a waste of money unless it starts pinging.

Smell the dipstick and see if there's gas in the oil, and make sure the choke isn't stuck.

 

I don't think the octane would be a factor but 92 actully burns slower than 87.

My truck has a 19 gallon tank and get about 100 miles to a tank as well. I don't run it 100% dry but I usually get anywhere from 6.5 to 9 mpg. Thats a built 460 and I think thats quite good mileage, the 9 is anyway. Unless you actually caculate the miles I would consider no way to deterimine if its good or bad.