What causes cracks on the side of tires?

[MasonMarie]

Tire sidewall cracks can be caused by two reasons: natural aging of the tire or impact damage. 1. Natural aging: During prolonged use, exposure to wind and sunlight causes the rubber to age naturally, resulting in cracks. This is a normal phenomenon. Generally, tires on vehicles older than 5 years will show cracks, which don't affect normal usage. However, if the cracks are dense enough to expose the inner tire, immediate replacement is necessary to prevent safety hazards. 2. Impact damage: When driving frequently on bumpy or gravel roads, tire impacts are unavoidable. This is also normal. Minor impacts don't affect normal usage. But severe impacts will reduce tire lifespan, requiring prompt replacement.