my '88 7.3 with a ZF 5 speed and 3.55ls and 235/85 R16 tires
using one quart of 10w-40 in each tank
bone stock
23Mpg hwy

 

Forgot to mention, I run 235/75/16 tires.

 

12 mpg. i think i have around a 3.55 rear.

 

Darn it, this should be 235/85/16.

 

84 F-250 X-cab 4x4 6.9/c-6 3.54 180,000mi at 55mph 18.4 NA, 19 Turbo

 

mine is an F250-HD, NA/7.3, E4OD, 3.55:1 rear end, big bracketed mirrors and the radiator is blocked off flush with the outer surface of the grill.

It has leaky injectors with heavy smoke on startup and that STINKY DIESEL smell all the time.

No idea how the compression is, as low compression in one cylinder could cause this.

Last time I checked it was 15 mpg.

I have a set of 92 van injectors that are rated at less HP than the pickup truck, so when they are installed I hope to get better mileage.

 

mileage varys flatland or mountains sea level or altitude,town or highway,it depends on where and how you drive them driving habits beeing a huge factor.

 

i guess i need to throw in a quart of 10w-40!

 

my friend who runs the local diesel shop told me to add a quart of any type of cheap engine one in each tank. It keeps the IP & inj. lubed to replace what we lost with ULSD
and will help replace some lost Fuel mileage.

You can't get as good of mileage with ULSD as you could with LSD

 

My 1988 F-350 4x4 3.55LS 7.3L C6 gets around 15mpg. It is usually hauling 100 gallons of fuel at all times. It is my regular tank and since fuel is so expensive I don't let it get to low. The mileage changes a little when I tow heavy but does not change with the plow on. My 1993 F-250 4x2 4.10LS 7.3L E4OD gets about the same mileage. The only saving grace is they are paid for and I can afford the fuel until tomorrow! LOL

 

i am looking at a 1991 f250 4x4 7.3 5spd. seller is telling me that he is getting 20-22 mpg empty. is this possible? rear end ratio is unknown. it is an old forestry service truck.

 

ive heard of folks gettin 20 with the right gearing and right foot usage....

 

how common is this? if this istrue that is better fuel mileage than the 1997 ford explorer sport 4x4 5spd that i currently drive.

 

I have a 93 E350 NA auto 3.54 rear 282,000 mls and I average 17 mpg driving around NYC all week. The best I've gotten on the highway is 22. I'm usually empty but haul 3-4k lbs at times and get about 16 mpg mixed empty and loaded local. I come off the scales empty at around 6500 lbs.

 

i don't get but 16-18 with my exploder.