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.

[AylaRose]

I've been driving for decades and often encounter cracks on the sidewalls of tires. The most common cause is tire aging—rubber hardens and becomes brittle over time, especially when parked under direct sunlight. Another reason is insufficient tire pressure; driving on underinflated tires increases sidewall stress, making them prone to cracking. Once, my car was parked roadside and splashed with chemical cleaners, which gradually caused cracks due to material corrosion. Deep cracks are dangerous—if they lead to a blowout at high speed, loss of control is likely. I recommend checking tire conditions every three months and using a tire pressure gauge to ensure proper inflation (around 2.5 bar for passenger cars). Don’t overlook this small detail. If cracks are shallow, they may be tolerable for city driving temporarily, but if deeper than 2mm, replace the tire promptly. When washing your car, rinse off road residues thoroughly to avoid exposing tires to corrosive liquids. Safety isn’t something to take lightly—addressing issues early saves major trouble.

[DelMason]

As the primary driver for my family, I pay close attention to tire safety. Sidewall cracks can range from minor to serious issues. Typically, they result from natural rubber aging, especially when the car is parked outdoors where UV exposure makes tires brittle and prone to cracking. Sometimes, driving with low tire pressure can cause the wheel to deform under load, leading to sidewall cracks under pressure. Deep cracks pose higher risks—they may cause air leaks or sudden blowouts, compromising vehicle control. During my weekly family commutes, I make it a habit to inspect the tires and feel the crack depth with my fingers. Superficial cracks are usually harmless, but deep ones warrant caution, particularly at highway speeds. Additionally, avoid scraping curbs or driving over debris-laden roads, as hard objects can scratch tires and leave cracks. Prevention is straightforward: check tire pressure monthly yourself and have mechanics inspect tires thoroughly during car washes. Don’t hesitate to replace old tires—safety always comes first.

[Alexander]

I've encountered tire sidewall cracks several times, mostly due to natural aging and hardening of tires after prolonged use, especially noticeable during high summer temperatures. Low tire pressure can also cause excessive sidewall compression leading to cracks. If the cracks aren't deep, they might not be problematic for short daily commutes, but deep cracks are dangerous as they may cause blowouts on highways. For my commuting routine, I use a simple tire pressure gauge monthly to check tire condition - looking, feeling, then inflating if needed. I always avoid parking in direct sunlight to minimize UV damage. Never use strong acidic cleaners when washing the car as they can corrode the tire surface. The safest approach is to replace old tires promptly.