Does Turning off the AC in a car make a difference?

Question

Yes, in my 89 chevy half ton it does. I have read all the other answers and most say it does not but I am here to tell you all my driving is in town and a lot of stops and starts plus I drive about 40mph everywhere. By not using my AC I have

saved3 miles per gallon. The math was done in the truck and I did it years ago before all this gas thing started so I have no reason to lie. The truck has a 305 V8 with throttlebody not FI.

Now this is in-town driving and a truck with older equipment but there is no question the AC takes about 9hp and even with the windows down I get the extra mileage. For all the new car drivers and the nay sayers check it for yourself as I did.

Answer 1

Yes, it does make a difference, but why did you bother answering a question if you are just going to answer it yourself?  How will you choose a best answer?  I don't think you can pick yourself!

Answer 2

I have wondered this myself...how much difference does it make, doesn't having the windows down create drag thus negating the benefit of no AC?

Answer 3

The rule of thumb is that you leave your windows open below forty mph and close them and turn on the AC above forty mph to get the best gas mileage.

Answer 4

when you put on your ac a second fan start, this mind that you are using more battery, your motor is working more, this mind that you are using more gas and your car run less, so, in my case, I don't use the AC for this reason. =)

Answer 5

With the windows down you would be getting resistance against what you're trying to go..  You'd be losing your milage all the same, but just not as nice.  Now if you save more gas with the windows who knows?  I don't do math studies like that.  But you're still putting an opposite force against you that's going to slow you down.  

I just leave my windows up and my AC off so when I get home to my crappy 81 degree apartment I think it feels like 70.  :D

Answer 6

A recent study was done about this comparing the use of A/C and having your windows down to see if either one of them made a difference. Yes the A/C made a difference but not enough to make a difference the checkbook. Having the windows down does not cause resistance either because its the car engineer's job to make sure the flow of air is not interrupted even if the windows are open.

Answer 7

yes it does i get a extra 60km from a full tank of gas when i turn my ac off.ac actually use a lot of the engine power