I get upper 9's with 1/2 city, and 1/2 highway. The best I have ever got was a camping trip back and forth from the Sierra. I got 11.5.

In my old '92 F250 Extended Cab 4x4, 460, 5-speed we got 14 mpg once unloaded on a 55 - 60mph hwy to Kanab Utah. My wife was driving and I was sleeping. I never ever got it to get that kind of mileage when I was driving.

 

Once, and once only mind you, I pushed almost 20mpg out of the carbed 429 that I originally had in my F250... I screwed up going to visit a friend out of town and took off thinking I would hit the last gas station about 10mi down the road. Got there and the place was CLOSED and like a big dummy I kept going, thinking I would find one open, instead every one I passed along the way were all locked up tight for the night!! 50 miles later I finally found one that was open (thankfully) and filled back up, but for 50 miles I babied that thing every bit I could... 45-50mph, and drove like a carton of eggs was under the gas peddle!! It didn't hurt that the cr on that motor was way high (11.8:1) and with 315s and 3.55 gears the motor was just above a fast idle at that speed. On the down side, punch it wide open a couple times and you could count on having used a 1/4 tank of fuel, LOL. In normal highway driving, 429 consistently got about 13-14mpg. The 460 thats in it now is much lower on its compression (10:1) is much friendlier to drive, last highway trip I made with it, it got 10mpg, 70mph towing a skiboat.

 

No, not you. You got a guilty conscience or something? I was referring to the old boy that claims 17 out of a 460.

 

Yeah I think the speedo was consistently reading higher than what I was actually doing. I was shocked to get that mpg out of that truck, but the engine was just barely above idle at those speeds.(guessing from the sound since I didnt have a tach)

 

I'd love to say I get 17mpg. I have a '95 crew cab dually. And was able to get 12mpg once doing 80mph down the highway no load. Its a giant brick. When I tow my horse trailer its a brick pulling a cinder block. I usually average 9-10 mpg.

 

Good one!!

 

My carbed 460 back when the truck was bone stock(86, 4 speed 4x4, 3.55 gears, saw 15 US MPG once, 243 miles pretty much steady state at 55mph on relatively flat ground.
Normal running around, it averaged 11-12.
On 38.5x11 Boggers with 4.10 gears and a mostly stock engine, it managed 9... LOL

 

Hey i know you. DTR.

 

I wasn't dissapointed with fuel economy on the f250 4wd efi 460, zf w/3.55 gear. On my first tank: 11.6mpg in mixed driving. Compared to many other vehicles, thats not very good, but my 4wd efi 300, E4OD w/ 3.55 yields only 12-14mpg, so I'm happy to make the small sacrifice in mpg for the huge increase in torque.

 

I'm getting between 6-8mpg on my F250 with EFI 460.