My wife likes to drive with the windows of our 2004 Chrysler Sebring open when the weather is warm. I say it costs no more fuel to close them and run the ac because at 60mph having open windows affects the aerodynamics of the car causing additional wind resistance. Am I right?
If the wife likes to drive with the windows open, then she should be encouraged to do so. A happy marriage is worth far more than the little potential difference in the fuel bill.Windows up at high speeds will save a little gas. If it’s not for very long, driving with the windows down won’t cost you a lot. Over long periods, it’s also more tiring to have the windows down. It seems to me that whoever does the long drives should determine if the windows are up or down. Why not do both? Then everybody is happy some of the time.
It’s really only on short trips of less than 1hr. I just don’t like the windows down anymore.
Differences are minimal, but the tests I’ve seen indicate that windows down with A/C off saves a little gas.
Windows up,AC off,that is if you can stand it.
Yes.
At higher speeds, where wind resistance comes into play, “windows up and AC on” tends to win.
At lower speeds, “windows down and AC off” tends to deliver the better mpg.
This has been discussed extensively. There are way too many factors to really know where the crossover point is for your car for any given driving condition.
Whatever the difference is, it’s going to be small. I can imagine it would be difficult for you to measure a difference.
However, the only really important concern is what Joseph Meehan wrote in his post above. Supporting your wife will return far higher dividends.
Do it your way for a year. Take the money you save an buy a nice cup of coffee. But make sure it is your wife’s favorite coffee drink. You will want to give to her because she is now annoyed with you.
Windows UP to lessenoise.
Better aerodynamics at high speed.
We use vent whenever possible with AC on intermittantly as needed.
(AC will not come on at high RPMs. Presumably to not break compressor shaft?)
Sometimes we allow the interior to get really hot and have a good sweat-out while driving home.
at 60 mph its a wash. Below 60 windows open uses less gas if AC is off. At 65 mph and above less wind drag saves fuel even with AC on. Someone is going to have to give in, this fight can go on for years. The difference in mpg is too small to measure in either case.
Can’t stand it. We live in Georgia.
Very true. It’s not an argument it’s more a matter of curiosity.
I’ll use the two most important words in a marriage, “Yes dear”.
Good idea about the vent. As for the sweat out, I live in Georgia and work in construction, I think I’ll pass.
That someone will be me now that I know the difference is minimal. Thanks.
At 70, the buffeting and drag are annoying…At 50, I like the windows down too…So at 70 I just keep them up and use the “Vent” position which provides good ventilation with no wind noise. I use the A/C when I NEED the A/C…
That depends. Old style air conditioners were very inefficient and took at least 5-6 HP to operate. And cars were square, so the air drag was enormous. Overall, the A/C off gave you better MPG at normal and higher highway speeds.
Today’s A/C units are very efficient, cars are more streamlined. Opening the windows results in a significant loss in mpg, so I would be inclined to close them at highway speed, but open them during city driving. Any speed over 55 or so dramatically increases air resistance, so I would then keep the windows shut.
Personally, I think comfort should take precedence over money; hope your wife covers her head with the windows open. The price of a hairdo is very difficult to recoup by driving with the windows open.
I agree. What ever it “costs” one way or another is immaterial to the debate. It should be just about comfort and irritation if there is any, to the other occupant. Try to compromise on those factors and leave aerodynamics and cost are out of it.
They did this on Mythbusters a year or two ago. At speeds above 45, windows up, a/c on was better than windows down, a/c off.