i have an old f-250 with a 351 windsor in it and am looking to fix it up but the gas mileage is terrible. My friend says it should be able to get about 16-18 mpg but it is barely getting 11 mpg.
if anyone knows of a way to do something to the engine or anything else that is on the truck to help it get better mpg it would be greatly appreciated if you told me.

 

I owned one myself an by rejetting the carb. an leaning it way out , an over advancing the ti
ming I was able to get 14 MPG hiway driving.

Sorry , I worked on a fleet of these trucks back in the early 80's, if you get 12 miles to a gallon your doing good . An if there a 4X4, an with a 4 bbl carb. an loaded heavy, load like a construction crew dont know where your friend got their info, buts theres no way in the world these ole girls will get 16-18 miles per gallon. even if you let them idle for a long period of time, they will still suck the fuel , nature of the beast...