Craig R., Niagara Falls

You may recall from science class that air expands when it is heated. Conversely, it contracts when it is cooled, so as the air temperature drops, so does the air pressure in your tires. Air pressure inside tires drops one to two pounds for every 10 degrees of outside temperature, according to the Rubber Manufacturers Association. You will get a correspondingly higher reading as the ambient temperature increases. Tire pressure also rises as you drive, especially at sustained highway speeds. That’s why you should check pressure levels after the vehicle has sat for an hour or more.Tire_cold

Underinflation causes a number of problems, including increased tire wear, lower fuel economy and diminished steering response, so it pays to check your tires year-round and keep them properly inflated.

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Answered by Rick Popely on March 12, 2010 in How Does That Work? | Permalink

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