Tires are subjected to one of the harshest environments experienced by any consumer product. In addition to being stretched millions of times as they roll through their life, tires are exposed to rain, brake dust, harsh chemicals and direct sunlight, as well as summer’s heat and winter’s cold. While a tire’s rubber compounds have anti-aging chemicals in their recipes, exposure to the elements will eventually cause rubber to lose some of its elasticity and allow surface cracks to appear.
The surface cracks that occasionally appear have been called many things. This could be known as weather checking, weather cracking, or ozone cracking. These small cracks typically develop in the sidewalls or at the base of the tread grooves. Depending on their severity, they may be cosmetic in nature if they do not extend past the rubber’s outer surface, or may be a reason to replace the tire if they reach deep into the rubber. Since all tires are made of rubber, all tires will eventually exhibit some type of cracking condition, usually late in their life. However, this cracking can be accelerated by too much exposure to heat, vehicle exhaust, ozone and sunlight, as well as electric generators and motors. For example, a vehicle parked outside instead of in a garage will constantly expose its tires to the rays of the sun, increasing the likelihood of cracking. Additionally, some sidewall cracking has been linked to abrasion from parking against a curb, or the excessive use of tire cleaners that inadvertently remove some of the tire’s anti-oxidants and anti-ozone protection during every cleaning procedure. Interestingly enough, when sun exposure or excessive cleaning is the cause of the small cracks, the sidewall of the tire facing outward will show damage, while the sidewall facing inward is rarely affected.
The anti-aging chemicals used in the rubber compounds are more effective when the tire is exercised on a frequent basis. The repeated stretching of the rubber compound actually helps resist cracks forming. The tires used on vehicles that are driven infrequently, or accumulate low annual mileage are more likely to experience cracking because long periods of parking or storage interrupt working the rubber. In addition to being an annoyance to show car owners, this condition often frustrates motor home and recreational vehicle owners who only take occasional trips and cannot even park their vehicle in a garage or shaded area.
The same types of cracks can also be caused by poor tire maintenance practices. Driving on a tire that was flat, or one that was underinflated or overloaded causes excessive stretching of the rubber compound, and may result in cracks that appear similar to the surface cracks mentioned above. If you notice any damage to the tires, bring the vehicle in, so we can inspect the tires for you.