Best fuel economy speed

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I drive the speed limit or just slightly above. The difference of a 1/2 mile per gallon or so is not worth my time or effort to slow down. My favorite follow up to a post like this is....YMMV.
I want to get where I am going. For some it is the journey and for some it is the destination. For me, it's the destination. I would rather be there! I very often travel at 70 or so and the difference between that and 55 is less than 1 MPG.

I usually run 64-70 and get 7mpg. I did 100 mile test at 45 mph on a rural WY road. Instead of seven I got 10 MPG but I did not want to take another day to get home.

Bet economy around 62 mph. But I drive whatever is comfortable. As said the difference between 7.5 MPG and 7 MPG ain't enough to sweat over.

Towing a toad for me is 1 mpg

Too many variables to give an answer.
Motor, transmission, rear end ratio, load, tire diameter, peak torque, all play into your answer.

I drive at 62 when possible, may drive a little faster going through metro areas my best mpg is at 55 but with a days driving 62 turns out to be 55 so 55 would turn out to be 45 which would add an hour to our 250 mile preferred travel distance.

59 MPH is where I get the best gas milage in my Winnebago gasser.

donn0128 wrote:
Too many variables to give an answer.
Motor, transmission, rear end ratio, load, tire diameter, peak torque, all play into your answer.

Exactly.

Back in our gasser days our V10 did better at 70 MPH than it did at 65 MPH. At 70 it was in its sweet spot, at 65 it struggled on even the smallest hills.

I also agree with the others that +/- 1/2 to 1 MPG isn't something I'm going to get too worked up over. Normally I want to get where I'm going.

Having said that I have found myself slowing down a bit lately. We just did a 1200 mile trip, I ran around 67 MPH most of the time.

For most vehicles with the frontal area of a motorhome the best fuel economy speed will be in the 35 mph to 50 mph range, which is not practical. So as slow as you can stand to run.