This woman claims she doesn’t need to add air to her tires when it’s cold. Experts have mixed feelings.
Girl math meets tire pressure
In a viral Instagram video, influencer Brittany Molfese shared how she handles car maintenance differently in the winter.
She shared that her car, which automatically reads the pressure in her tires, often alerts her on winter mornings that her tire pressure is low, but Molfese knows that information isn’t so cut and dry.
“Girl math is having your car yell at you for the tire pressure, but you know the day will warm up and so will your tires so you’ll be fine once the molecules expand,” Molfese said.
So, Molfese doesn’t add air when her car tells her too because she’s noticed that the tire pressure goes back to the right amount once the day warms up.
Why do tires deflate in the cold?
It’s not that they deflate; it’s a bit more sciencey than that.
When it’s cold out, the molecules in the air move slower and stay closer together, giving the appearance of a smaller, more deflated tire. When it warms up, those same molecules start to move faster and further away from each other, giving the appearance of an expanded tire, Firestone Complete Auto Care explained.
In short: “When the temperature is high, the air in your tires takes up more volume, whereas when the temperature is cold, the air takes up less volume,” Lexus explains.
For every 10℉ temperature change, your tire loses or gains about 1-2 PSI ((pounds per square inch), so a 20℉ drop could lose you up to 4 PSI.
Should you still put air in your tires in the cold?
You’ll have to consult your mechanic for exact information, but it’ll remain cold in your area. You should add air, but if the temperature will change significantly throughout the day, the answer may vary.
Lexus recommends adding air to your tire in the wintertime while the tires are still cold to ensure they aren’t underinflated when driving in cooler temperatures.
Underinflated tires, or tires with low pressure can lead to the following:
- Less steering control
- More wear on the tires
- Lower gas efficiency
- Increased brake time (that can lead to more skids)
Commenters react
“Yeah no… unfortunately I can’t afford $400-$500 for new tires that often. Air is free. Tire pressure is checked cold,” a top comment, with more than 16,000 likes read.
“I just drive faster so they heat up sooner,” a person said.
“All while keeping mechanics and tire techs employed … thankyou!” another wrote.
The Daily Dot reached out to Molfese for comment via email and Instagram direct message.
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