Real MPGs for your rig?


Driving around town 11.2
Long trip Houston to Crested Bute, CO average 10.2 mpg at 75/ 85 mph. Four people with ski trip luggage.

E350 EB 4x4 5.4 with 206k miles


Expedition Leader
Latest tank - Highway: 210 miles / 13 US gal = 16.2 mpg +/- or 14.8 l/100 km. Traveling on the I5 @ 70ish mph average.

I'm sure economy would have been much better at 65 mph, but this trip it always seemed we were trying to catch up to the rest of our group that were hours ahead of us.
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That kinda mileage would pay for a 6.9/7.3 non PowerStroke swap in short order. The 4.10 geared and carb'd 400Ms, 460s, Dodge 400s, and 454s were the worst guzzling motors I've ever driven esp when coupled to non OD, non lock-up automatics............but they got the same 6-9 mpgs regardless of what you are doing, and they last forever with minimal maintenance.
If she's just a driver and doesn't tow a heavily loaded trailer all the time, regearing to 3.5x or numerically lower, or an auxilliary OD unit can work if it does see big loads, can improve the gas station situation a bit.
Considering just that in a 1990 460 powered E250 Quigley. Thanks for the input.


1989 E-150 2wd Sportsmobile Penthouse with just paneling and insulation, no interior fixtures. 4.9L, C6, 3.08 R&P, 225/75-16 tires. I keep it full of construction tools. Typical daily weight is 6-7,000 lbs.

17 mpg highway, 14 city. I drive 65ish on the interstate, just get to the speed she's comfortable and hold the pedal steady mostly. Drops to 60 on most hills and hits 70 or so going down.

Expecting the M5OD swap (with 3.55 R&P) I'm working on to improve mileage a bit (20 mpg hwy is my guess) but mostly doing it for fun and to keep a 30 year old automatic transmission from ruining my day.
This helps me.... thinking about a 4.9 in a 1990 e250.


This helps me.... thinking about a 4.9 in a 1990 e250.
That E4OD you're considering with 3.54s and 245/70-16s is very very similar to my plan of an M5OD and 3.55s with my 225/75-16s. I'll turn a bit more RPM with my .80 OD vs your. 71. At 70 mph I'll be at 2,281 and you'll be at 2,004. Bet you'll be around 19 mpg hwy and 15 or so in town. If I ever get to travel the Panamerican I'll probably go to 235/85-16 for a touch more ground clearance and better all-terrain tread availability. That'll drop me to 2,105 rpm at 70 mph but that extra inch of ground clearance and higher rolling resistance will probably hurt mileage a full digit or so.