Most fuel efficient speed?

Since the gas prices have been killing me lately and I have a good 45 minute commute...

In your opinion, what speed is the most fuel efficient on the highway?

 

IMO, it's not speed as much as it's RPM's I do pretty well keeping the motor under 2K

 

Any speed , downhill

 

And what ever you do, don't get a bro lean. All that up hill driving will kill your mpg's.

 

...with a tailwind

 

both ways

 

55

 

35-55 MPH is the butter zone, with the instant MPG is around 30 MPG-ish. I'd avoid the interstates that go faster than 65 MPH. What kills it to an average 22 on my truck is the take offs, idling and hills.

 

45-50. Always coast to a stop if possible. Any time you hit the brakes you are wasting energy already expended.

 

When the truck slips into final gear, that is your best mpg. 40 - 45 MPH is the best gas mileage and my little car app confirms that.

 

As stated above ... RPMs .... 2000 & under

 

Yep
Lowest speed in the highest gear.



RPM is only half of it.

 

Its mostly dependent on throttle position. Some guys tested this a few years ago. Least throttle position below 60mph i believe

 

Get a Scan|Ultra guage and use the instant mpg reading to fnd out for you. Too much variation in truck, road and weather conditions for one answer to be totally correct for you. I will show higher mpg's at a steady 55 then at 40 (both in high gear), so you need a bit o' data to decide.

 

This

 

Straight out highway 65 - 70 mph I'm getting around 20 mpg. Back roads with hills but long runs between "stops" I get 23 almost 24 mpg plus. That's doing about 50 or so. I found 2000 rpm seems to be sweet spot regardless of speed. Hills kill it as do stops and starts. Also watching the UltraGauge even a higher gear with a lower speed isn't ideal. An efficient engine speed seems to be the determining factor.

I drive a manual shift 4 banger 4x4 regular cab.

Mileage dropped recently. Winter gas I guess ???

 

RPM's don't matter as much as load on the motor/throttle position

 

Huh. Maybe it was thanksgiving dinner that trashed my miileage.

 

100 MPH downhill coasting

 

in neutral