Why does a tire leak air without a puncture?

[ElainaAnn]

Tire leaks can occur due to poor repairs, aging rubber of the valve stem, or the valve core not being reset after checking tire pressure. These conditions can lead to slow air leakage. Tires naturally lose air over time because a perfect seal between the tire and the wheel rim is impossible. Factors like thermal expansion and contraction, as well as vibrations during use, cause very slow air leakage through the gaps between the rim and the tire. Here is some relevant information about tires: 1. Pay attention to the tire's expiration date: The sidewall of the tire has a four-digit number indicating the manufacturing date, with the first two digits representing the week and the last two the year. Generally, tires should not be used for more than 3 years or exceed 60,000 kilometers in mileage. 2. Monitor the sidewall: As tire rubber ages, deep cracks may appear on the sidewall. However, as long as the sidewall hasn't been impacted and the cords remain intact, the tire can still be used. The triangular marks on the tire sidewall can help locate a raised area in the tread grooves, indicating the actual wear limit of the tire. That value should be greater than 1.6 millimeters.