MPG, Speed and Overdrive


Precision Fit
Oct 23, 2009
Citrus Heights & Tahoe
First Name
Willys Model
  1. Pickup
Willys Year:
  1. 1954
Bought my 1st Willys in parts so do not have any benchmark for what I should expect MPG to be (stock pu w/ 226 &3psd no/OD).
Can anyone give me a clue as to what I can expect City/Hiway?
With addition of overdrive I know wear & tear will decrease as will top speed (wow)
What increase in MPG and top speed can I expect with adding an overdrive?
Need to do the math on cost of fuel VS OD.

Did they do MPG back then?

I know the overdrive will help it a great deal......

I used to run my CJ-5 with the V-6 and a 3 speed. I was able to run 60-65 without any problems. just didn't feel safe faster than that with the extra short wheel base.....
Eric, I have to wonder if you'll get a viable answer to that question. Most of us that have been playing with these for a while are more interested in trying to keep them running rather than worry about mileage., I did a haphazard check on mine one time and it came out to about 9 mpg. It's a stock, worn out SH226. I should have kept better records seeing as how the fuel gage never works. :) I'd drive it even it only got 5mpg though. :)
Steve, it was "homewood4" that asked about the MPG's.
I know personally for my new to me '62 and the Ford 351W V8 in it that I will be lucky to pass a gas station once I get it back on the road..... I look at like this as a long time Jeep owner "sucks gas, gets nowhere fast".
Without OD and per my GPS, I got my truck up to 62 mph and the gas pedal was on the floor. It wasn't lack of power keeping me from going faster... I just ran out of gear/RPM. I only did that speed for about a half mile. I thought I was going to have the crankshaft in my lap if I did it any longer. It's never been that fast again. It was cool to "drive it at speed" though.

Per my GPS my truck likes to cruise at 42 mph. I don't know what RPM that is, but 50+mph just sounds like it's wound out. I hope I can find an OD for mine soon. I don't want to transplant a different engine and trans... but I would like to get somewhere in relatively decent time. :)
I don't know if O.D. will really help all that much in the miles per gallon dept. I have a mostly stock 59 wagon with the 226 and could only push it up to 55 mph without feeling like I was over reving it, so I put in an overdrive and can easily do 65, I can push up to 70-75 but it just starts to run out of juice at that speed, I put in a 2 barrel manifold/carb to try to up the power a little and went with 16 inch rims and a little taller tires to get the speedometer to read right (checked with G.P.S.) I think my replacement speedometer may have come out of a truck and they may be geared a little different (I'm not sure about that though). I get about 14 mpg with mixed city/highway driving