Cold weather can take a real toll on your gas mileage. As I pointed out in an earlier post about winter gas prices, gas companies sell a different fuel blend in the winter, which produces less power. That’s not the whole story, though. There are a number of other reasons why you have to gas up more once it gets cold out.
The Impact of Frigid Temperature on Your Auto
The first is that your engine has to work harder in the cold. First of all, the oil that lubricates your engine gets thicker when it’s cold, which means there’s more friction on the moving engine parts. You also probably use more electric accessories during the winter. Think of your heating fan, lights, defrosters, windshield wipers, and all the other parts that draw on the battery. You run a lot of these more often in the winter. That drains the battery (which already drains more easily in cold conditions) and means the alternator has to work harder.
The grip of your tires also contributes to your fuel use. As tires roll, they actually flex a bit to make a contact patch with the road. That helps you get more grip. Rubber gets stiffer in the cold, so it doesn’t flex as well. That means they’ll have a smaller contact patch on the road and less grip. That means you have to use more power just to get going. If your wheels slip, then you’re really wasting power. The engine’s pushing but you aren’t getting anywhere.