I am getting 10mpg in my 91 F350 4x4, is that about average?

 

You need to give more info. What transmission? What axle ratio? Stock tires? Towing? Mainly highway or city?
How are you calculating your MPG?

 

i get 13-15 outta my 88 f250 4x4 7.3LNA 3.55 5 speed. and im running a 315,75,16

 

What they said, but I would say you're probably not getting close to what you should. A lot of people can get around 17-18 empty on the highway at 55 with 4.10's and 65-70 with 3.55's

 

14.63 MPG @ 44 tanks.
(click pic for details.)

other info of interest;
this is #1 priority;
http://www.oilburners.net/wiki/tiki-...hp?articleId=7
some suggestions here are #2 after the engine is properly tuned up;
https://www.ford-trucks.com/forums/9...ing-25mpg.html

 

it's a 5 speed, stock tires, axle ratio??, average 10mpg,

I fill the tanks, reset trip meter,drive 1 tank near empty, refuel, miles/gallons=mpg

someone said my transfer pump was not timed correctly, it clatters pretty loud

 

That would be injector pump. I bet if you time it properly, you'll get more from it. Also, just in my own case, my 91 suffers from a bad case to speedo error, especially as you go faster. At 45, I'm doing 50. At 60 I'm doing 69. I've found that on a 180 mile road trip to central oregon with no stops, my odometer only reads out 135 miles. Just that alone will throw your mileage calcs off big time!

 

i never use the odo......oh wait yeah it doesnt work. lol. i use gps and google earth for exact trip mileage! 1989 7.3 idi C6 4.10's with fresh pump and injectors can pull 17+ empty at 55. sad that my 2005 V6 5sp auto minivan cant do that....die kia van....die!!! haha

 

Pre-turbo, I was getting 17-20 mpg putting along at 60mph with the truck in my sig. Haven't ran enough tanks yet to give an average with my new setup.

 

thank you for all the help, it is my first desiel

 

i was mad when i was getting 13 out of my setup with the old pump and i have a 3sp, you should expect more!!

 

wreck,where do you find those low cost rebuilt injectors from U-haul?
i found 'em.
for 70 bucks for 8,im gunna see what happens.

 

so would i be crazy to expect about 17 mpg average with my truck(94, 7.3 turbo idi, e4od, 2wd, stock tire size, and about 70 to 80% highway)?

 

i don't think that would be crazy.my f250 4wd dually box truck could see 17 mpg @ 55 mph running empty on the hwy.i know cus iv done it once,and that was only for a short while running out there.then the rest of the tank was rural stop and go crap again lol.

there are lots of reports of the 2wd,factory bed,srw trucks pushing high teens to 20mpg (on summer blend) around here.

 

what gear ratio? synthetic or conventional gear oil? swamper or highway tires?