With winter comes shorter days, darker nights, snow, and road salt — all of which can be hard on you and your car. Low temperatures can expose a weak battery, worn out wiper blades or dim headlights can make it hard to see when the sun sets early, and bald tires can make it nearly impossible to get traction. But one thing you may find yourself wondering every winter, is “Why do my tires seem to lose pressure in the cold?”
As cold weather settles in, you may notice your vehicle’s tire pressure dropping almost as quickly as the temperature does. Colder temperatures mean that the air in your tires becomes denser as the molecules begin grouping together and moving more slowly. As air becomes denser, its volume decreases, causing the pressure inside a vehicle’s tires to drop. Tire pressure drops approximately 1 pound per square inch, or PSI, for every 10°F drop in temperature. That means that a tire with 30 pounds of pressure at 70 degrees may drop to 26 pounds at 30 degrees, often triggering the tire pressure warning light in your vehicle.
You may have also seen the warning light on your dashboard turn off after driving a few miles. Tires generate heat as you drive due to friction caused by their contact with the road’s surface. As the tires heat up, the air inside the tires also gets warmer, which causes the air to expand and the pressure inside your tire to reach an acceptable pressure to turn off the warning light. Even if the light has turned off, you should still plan to fill your tires with air as soon as possible to ensure proper tire pressure the next time they cool down.
Driving with low tire pressure can be dangerous, as under-inflated tires have more contact with the ground, increasing the likelihood of your tires overheating. This excess contact and friction, especially on the sidewalls of your tires, can cause premature wear, tire tread separation, and even blowouts. You should maintain your tire pressure according to tire specifications throughout the winter months to ensure your car drives at its best. Low tire pressure may also cause you to experience decreased braking ability, skidding, poor fuel economy, or a shorter lifespan of your tires.
Improve gas mileage, decrease tire wear, and prolong the life of your vehicle’s wheels by maintaining the correct tire pressure levels. O’Reilly Auto Parts has informational videos and step-by-step instructions, as well as the products you need for both maintenance tasks or a larger repair to keep you safe while driving.
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