My dad has a 2003 F350 with a 7.3 and we only get about 12 mpg. It went to georgia to get my 78 F250, and got the same mpg empty as it did full, which also was 12. We were told that it got better mileage then the gas motors, so anyone know whats up?

 

The milage does sound a bit low. But should improve as you get more miles on it. What are your gears? 4.1, 3.73 or? How heavy is your foot? There are a number of things you can do to improve the milage. Larger exhaust, cold air intake, computer chip, fuel additive etc. I was at 12.5-13.5 mpg when my 01 350 was new. After the mods and now 56,000 miles I now get 17 plus. (not towing)

 

I get about 16.5Mpg or 620 miles per tank and i have a heavy foot but when my PSD was new it to didn't get the best milage. about 12mpg. My best speed is 72MPH at 2200 Rpm

 

What size diesel tank you have?

 

They say it's a 38 Gal but if I fill it to the cap i have put 36 gallons in it. my last tank full was 34.530 gallons and I drove 575 miles city/hwy daily driving 16 mpg

 

You may be getting air in the fuel system. Try a search for "fuel mods" or "pre-pump mods", or e-mail me and I'll give you a brief overview of the symptoms and the cure.

 

Wow, I have a 94.5 PSD and I get 21mpg + on the highway. But mine is just broke in. 252,516mi.

Tyler
94 F-250 PSD 5 speed
95 F-150 302 5 speed

 

I have a '00 7.3 and just got 21 mpg. I average always above 17, and she's bone stock.

 

If you have the wrong oil in a PSD or low oil, or old oil it will get terrible fuel mileage. Mine gets 17 -18 mpg on a good day, but when the oil gets low, or old I am lucky to get 12, it is usually below that.

Theo

 

I just returned from a 750 mile trip to south dakota with 3 passengers and a moderate load in the bed of my 02 f 350 psd.My fuel economy was great I averaged 17.5 mpg traveling 80 to 85 mph and the a/c blowing cold.

 

I agree with every one else. Your mileage should improve with some more miles on her. I only buy fuel at the truck stop and use a fuel additive. Most of the truck stops now have a lane with a smaller nozzle for pick ups now a days. It is usualy the closet one to the door. My average is about 17/18 but during the winter it drops to about 14(winterized fuel).

 

I have never had a diesel before. I have been told about the mileage many times over. I have also been told about the great pulling power. About 6 weeks ago I picked up a 2000 F-250 4wd PSD with 3:73's and 18k on the clock. I get high 15 empty and 10.9 towing 7100 lbs. I have done the under 2000 rpm thing with no help. I'm not sure if it will get better with more miles but I think maybe something else is wrong. It pulls the trailer ok but not as good as I thought it would. It has a new air and fuel filter and I get 15lbs of boost empty (looking at it on NGS). The fuel pump sounds kinda funny with the key on (engine off). I don't want to buy a chip and exhaust without fixing what could be wrong now. It has no codes and runs good just poor mileage and less that I think it should have pulling. Thanks for any help you can give.
Jeff Hamilton

 

That is just not right.
My 03 7.3 4x4 F-350 with an AUTO has been getting 17-18 mpg I have a lead foot and lately have been running the ac constantly.
By lead foot I mean I accelerate quite briskly from every stop but do try to stay at 70 to keep the rpm's at 2K.
I have 3.73's and this is mixed driving but very little stop and go (it's my commuter vehicle and only plays truck on the weekends)

My first few thousand miles on winter fuel and her not broken in were pretty crappy maybe you just need a few more miles, I just hit 10K last week.