String wind & effect on mpg

[MavMeister25]

Was just driving 70-80 mph on a toll road in the same direction as a strong, steady wind. The instrument cluster said 42 mph. I was thinking…great! Then on the return trip later on, driving against the headwind, the reading said 29 mpg!

Made me realize that, especially as you approach speeds over 70, wind is a MASSIVE factor in mpg.

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[Maverick Country Club]

100%
I think when you are going into a strong wind the tow mode helps with the mileage.

 

[Cherokee]

Made me realize that, especially as you approach speeds over 70, wind is a MASSIVE factor in mpg.

Old knowledge,

 

[Cancunbadlands]

100% it is

 

[Delbert]

The difference between a Prius and a truck.

 

[Timothyd]

Was just driving 70-80 mph on a toll road in the same direction as a strong, steady wind. The instrument cluster said 42 mph. I was thinking…great! Then on the return trip later on, driving against the headwind, the reading said 29 mpg!

Made me realize that, especially as you approach speeds over 70, wind is a MASSIVE factor in mpg.

Slow down?

 

[Gaidheal]

Made me realize that, especially as you approach speeds over 70, wind is a MASSIVE factor in mpg.

It's a drag. Or rather the drag.

Drag (over simplified) goes up proportional to the velocity squared..

I think it was TopGear that did an episode with one of the Bugatti super cars with ~1000 hp. Paraphrasing, but the premise was that the driver commented while he was cruising at 100 mph it was taking about 100 HP to maintain 100 mph and it was going to use the remaining 900 HP to get up to 200 mph, which he then demonstrated.

The faster you go you need an increasing amount of power to go even faster. A surprising amount to go just a little faster. A road vehicle's achievable speed can be considered as its ability to push the air out of the way (ignoring gearing limitations, etc) ... and if the wind is coming at your it makes it that much harder.

"Harder" in this case means more power, which is more fuel.

 

[ScottyC]

 

[MavMeister25]

Slow down?

Speed limit is 85.

 

[MavStangVa]

I would cut all the strings off that are causing the wind effect

 

[MavMeister25]

Old knowledge,

Nihil novum sub sole.

What can I say? I guess you know everything. I was sharing an experience and my surprise in regard to it.

 

[Probity]

Aerodynamic drag certainly takes a toll on mpg’s. But even in the not-as-cold southern (as opposed to northern) US, somewhat surprising numbers (to me) on the outsized contribution of higher air density with colder ambient air temps to reduced fuel economy – it’s a big factor too.

In winter, everything working against you (winter blend fuel, higher air density with colder ambient air, longer engine warmup times [OK maybe not so much of that in southern Florida…]. Add in 70+mph going into a headwind and hello to more frequent gas station stops.
Atmospheric Effects on Aerodynamic Drag
Fuel Economy in Cold Weather | Department of Energy
Learn the facts: Cold weather effects on fuel efficiency

 

[Master Blaster]

85mph is stupid in a truck. It has the aerodynamics of a brick, not a Ferrari. Whoever decided the speed limits in your area is a moron.

 

[Probity]

85mph is stupid in a truck. It has the aerodynamics of a brick, not a Ferrari. Whoever decided the speed limits in your area is a moron.

Gee, don't be shy, tell us how you really feel.......

 

[surfstar]

Was just driving 70-80 mph on a toll road in the same direction as a strong, steady wind. The instrument cluster said 42 mph. I was thinking…great! Then on the return trip later on, driving against the headwind, the reading said 29 mpg!

Made me realize that, especially as you approach speeds over 70, wind is a MASSIVE factor in mpg.

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