Ford 7.3 mileage, pure highway.. experience?

[Buliwyf]

I think the later Superduties only need a scantool to reset your odometer for larger tires and gears. At least that's all my 2004 Mach1 needed.

Gps may still be more accurate. I just keep track to keep it close. I don't expect accurate numbers.

 

[lllateralus]

(answering the post about using the odometer as mileage indicator)

No.. I am aware of the tire size difference. I know exactly how long my actual round trip to work and back is from driving my other vehicle(s), and my handheld Garmin GPS.

 

[dp7197]

Stock tires from day 1 - 235/85R16s. The 3.55 gears make a big difference.

 

[Flagster]

my gfs 7.3l stock SCSB gets 20-25mpg but she drives like a girl...

 

[wagoneercraig]

Just checking . Been known to do things like that myself . Those MPG's are pretty impressive numbers for that size of a truck .

 

[City Cruzer]

I second what High Country said. Slower is not always better. I ran my 96 PSD, has a spoiler btw, at low RPMS for a full tank, 32 gallons of mixed driving. I kept it at 60 mph or below, easy accellerating in thew city, below 2000 rpm at all times. I was totally expecting to see at least 19mpg. I was completely surprised to find that running it like that produced the worst mpg I've seen, around 15. Now I'm back to running it at about 63 mph and 2200 rpm and I'm seeing just below 17. I'm not sure if its momemtum or if the engine is more efficient. I'm on a quest to see 18 one day.

 

[McZippie]

2001 Excursion 7.3, 3.73, everything stock, 170K, at 65mph get about 17mpg.... FWIW get about 13mpg at 75mph towing 5000lbs.

 

[TurboChris]

My 01 F250, running 38" tires, 4.56's and a DP Tuner adjustable chip would consistently get 18 running 65-70 on the freeway.

 

[IdaSHO]

This old PSD routinely gets 18-20 mpg empty on the highway.

With the camper on it, fully loaded I see 12-16mpg Loaded she sits just shy of 10k lbs.

260k miles, auto trans, 4:10 gears, 4x4

Wearing factory sized tires I keep it right around 60mph
That seems to be the happy spot for this 7.3 Right around 2200rpm IIRC

Wind it up above 70mph and it REALLY starts to drink fuel.
Still better mileage than any big block gas motor at that speed though. :coffeedrink:

 

[cnynrat]

Our stock 1999 7.3l Super Duty gets 17-19 MPG on the highway unloaded. It's a 4x4, supercab, long bed.

 

[cnynrat]

Not relevant to the OP's question, but I might add that we get 11-13 mpg on the highway carrying a 3000# Bigfoot camper.

 

[MicroBird]

It's probably been said, but I think one 40 mile trip is not enough to calculate your mpg. My diesel Excursion got about 19 @ 60mph. But an Excursion doesn't have a pickup bed. I'm sure a tonneau cover or something similar would help. I had 3.73s also, but stock height and stock tires.