What is Dry Rot and How Does it Affect Tires?

If you've ever driven on old tires, you've probably noticed small cracks forming on the sidewalls, and even between the treads, of your tires.

Cracks in tires appear for a variety of reasons, such as ageing, exposure to extreme weather conditions, improper use or maintenance, or overloading.

Cracks in tires can be dangerous, depending on their extent and location.

Dry tire rot, also known as sidewall weathering, is a visible crack in the tread or sidewall of a tire, caused by the decomposition of the tire's rubber compounds.

What causes sidewall weathering?

Cracks are a sign that the rubber in your tires is beginning to degrade. This is largely due to exposure to UV rays, chemicals and other elements that slowly break down the tire's compounds and reduce the rubber's flexibility over time. The result is a loss in your vehicle's manoeuvrability.

As this flexibility diminishes, cracks appear. Once cracks appear, it's only a matter of time before the tire reaches the end of its life and needs replacing. Even small cracks will continue to develop as the tire wears, particularly as the flexibility of the rubber deteriorates. If left unchecked, cracks will eventually cause the tire to burst, i.e. the sidewall will break, rendering the tire unusable.

Here are a few factors to consider when it comes to tire cracks.

If the cracks are shallow and of limited length, they may not pose an immediate danger. On the other hand, deep or extensive cracks can weaken the tire's structure, compromising its integrity and increasing the risk of bursting or sudden failure.

A very important point is the location of the cracks. If they are deep or extensive, they can weaken the tire's structure, compromise its integrity and increase the risk of bursting or sudden failure: sidewall cracks are of particular concern, as they may indicate structural damage. Sidewall cracks can lead to a loss of air pressure, reduced tire strength and an increased risk of bursting while driving.

Cracks in the tire tread can affect grip, particularly on wet or slippery surfaces. Reduced grip can compromise braking and handling, increasing the risk of accidents and passenger safety.

Are Dry Rot Tires Dangerous?

Yes, dry rot on tires is dangerous. It is literally dry decay, which causes tread area and sidewall cracks. These cracks can cause air pressure leaks, leaving flat tires behind.

However, if the cracks of dry rotting tires open up suddenly, it can easily end up in a blown-out tire.

How can I prevent my tires from being damaged by the elements?

Tires naturally degrade over time, even with minimal use. If a tire is old and cracked, it may be more likely to burst. Poor maintenance, such as underinflation or excessive exposure to heat, can accelerate the appearance of cracks.

The best way to prevent tires from cracking is to protect them as much as possible. The sun, water and salt on winter roads can accelerate the degradation of tire rubber and cause cracking.

To maximize the life of your tires and avoid cracking, follow these tips:

• Whenever possible, store your vehicle in a garage, out of direct sunlight.

• Whenever possible, remove snow and mud from tires after driving. Do not leave tires in standing water.

• Do not store tires at extremely high temperatures.

• Don't leave your vehicle stationary for too long. A stationary tire can crack more quickly. Even if you don't need to use your vehicle, run it every few days to get the tires rolling and work the rubber.

Bear in mind that even with the best care, your vehicle's tires won't last forever. Most tire manufacturers give each tire an expiration date of six to eight years after manufacture, due to the inevitable degradation of the tire rubber.

To find out the date of manufacture of your tire, look at the sidewall and you'll find a series of numbers printed on the side of the tire. The last four digits are a numerical code representing the date of manufacture. The first two digits represent the week in which the tire was manufactured, and the last two the year.

To ensure your safety on the road, we recommend that you inspect your tires regularly for any signs of cracks or damage. If you notice any significant cracks, particularly on the sidewalls, or if you have any doubts about the condition of your tires, we recommend that you have them checked by a qualified professional near you, or contact a PMCtire expert. He will be able to assess the severity of the cracks and advise you on the necessity of replacing your tires.