I would like to get opinion on the gas mileage for F 350 1999 with 5.4 L engine.
I just drove it for 400 miles on tank full. 200 mile miles on 1/2 tank and 200 mile back home the rest of the way. The tank hold about 30 gal.
I would think I should get better mileage. The ruck has new plugs , and one new COP , new oil change . Was not pulling anything, or loaded . It has a light utility bed empty. I was going about 70- 72 MPH. In fact the the entire trip was Hyw driven with over drive on and the Tach was around 2200 rpm

Any guidance as how to improve the MPG.

 

400 miles / 30 gallons = 13.33 MPG. That's not bad at all.

 

Yep, that actually sounds pretty decent, especially with winter blend gas(not sure where you live though..?) I've been getting 13-14 this winter.. was 14-15 last summer.

My record high so far is 17.6 (all interstate) and record low is 10.3 (towing).

 

You must divide miles driven by gallons used to tell millage or you are just shooting in the dark. Long bed 38 gallon, short bed 30. SD with 8 0r 10 gas will get 13 on highway and 10 around town. 4X2 may do a scosch better. 08 with 6.4 around 11 in all around driving my buddy tells me. But gas is pretty much free now so just drive and enjoy. Bottled water is 2$ a litter so that is higher then a kite and way over priced. Big water is so much more corrupt then big oil. Probably the tree hugging liberal left.

 

The most effective way to improve your mileage is to drive slower at a steady speed. I know, ain't what anybody wants to hear, but it's true. I seldom drive over 60 MPH in my F150, and get a consistent 15 mpg in mixed driving, a little better at steady highway driving at 60 MPH.