Tips on how to improve gas mileage

Step 6 Windows and AC

During the summertime avoid using your air conditioning as much as possible. It puts a lot of load on your car and uses lots of gas. Instead open your windows. Windows cause drag that can also decrease mileage, but not as much as your ac.
In the winter using your heater doesn't affect your mileage, it can actually help keep the engine cool on warmer days.

Comments

[Walis]

The thing is that AC takes 5 - 10kW from the engine power anytime, no matter if you go slow or fast. Open windows change the aerodynamical resistance of the vehicle, but this depends on your speed. So I would say - leave the windows open until you go faster on the highway.

[superdudemanguy]

The threshold for MOST vehicles in terms of window drag is 50 mph. Therefore for best results use the AC on the highway while using cruise control at 55. Realistically rolling down the windows is best in all non highway driving.

[swsmailman]

i guess you didn't see the episode where mythbusters proved that it is better to have the ac on instead of having the windows rolled down. plus, just use the vent setting on your truck, i have the same one only older but the AC pretty much the same.

[tictac24]

Actually, it was proved the other way. At 55 mph, it's more fuel efficient to have the windows open than the AC cranked up. So, unless you're going like 65+ (which isn't a fuel efficient speed in the first place) it's better to have your windows down.

[LinuxH4x0r]

Thanks, yeah I heard the same thing, but a little slower