i know this is old, but i know a guy that is getting 27 mpg with the 7.3. and he is all stock. You can say what you want, i have no way to prove this

 

best i have ever got on one tank was 24.3, but that was when we had the good diesel, maybe he saw 27 while going down hill,

 

i can get my 1993 mercury grand marquis to hit over 100 mpg in neutral doing 80 down a good hill.......

 

 

I can hit an instantaneous mpg of nearly 30 if I reset my computer mpg calculator while already cruising at 55 mph on the hwy

other than that --- I guarantee ya everyone would want proof of some sort!

 

Well, I have a 99 7.3 Powerstroke and I have gotten almost 28 miles per gallon. BUT- my rig is a 2WD Regular cab and lowered with an intake, 4" straight pipe, and Edge Evo. With the tailgate down I can average 27-29 mpg at around 65 mph. With a taller truck and the added drag, I am not sure this truck could achieve that level of efficiency.

 

Powerstroke 7.3 @ 27 mpg = Bullshiticus Maximus

 

Oh yeah? Read it and weep fellas,
I finally saw that it is possible, found these articles a few months ago when I got MPG crazy.

1997 Dodge Ram 3500 Dualie Cummins - Diesel Power Magazine

That's a 12V Cummins dually that gets 30mpg.

And this:

2000 Ford F350 Power Stroke Diesel Truck Mileage - Diesel Power Magazine

That's a Powerstroke 7.3L F350 2WD that gets 26mpg.

---AutoMerged DoublePost---

You should check out the second article I posted - similar truck to yours, maybe there's a couple more ideas you might see.

 

Hey, thanks K50. I can't help but laugh at mr chief engineer and his comment- I live just North of Sacramento and can go to LA and back on one 35 gallon fill up and still have almost 1/8 of a tank left. Here ya go chief - 820 miles/(35*0.875)=26.78 avg mpg. My 99 dodge can do better. Obviously this is just cruising the speed limit and tail gates down, no load.

 

my personal best was close to 22 thats hand calculated keepin it around 62mph hwy and taking it easy one of my friends had gotten 23.8 at one time and he was just tring to see what he could get for best milage niether one of these trucks had a lift at that time so you can knock off 2 mpg at least for that both have air and exhaust mods and chip or mod I agree he needs to rethink how he is calculating it the 7.3 is good but ive never even heard of 27 mpg on a 7.3