What is Dry Rot on the Tires

Dry Rot

Tire dry rot refers to the cracking and splitting that can occur in the sidewalls or treads of rubber tires as the rubber ages and becomes brittle. It is also known as sidewall cracking. Ozone and ultraviolet light are the primary environmental causes of tire dry rot. Tire manufacturers blend chemical ingredients into the tire during the manufacturing process in an effort to combat dry rot caused by ozone and UV exposure. Carbon black is added to the rubber to protect the tires from UV light. Waxes are added to the rubber during tire manufacturing to protect the tire against damage from ozone. If the vehicle is left to sit, the tires may develop dry rot. Make sure to check the tires regularly for any issues they might have.

Vintage and classic cars are particularly at risk for tire dry rot because they are typically driven infrequently, and may be stored for months at a time. Also, camper, RV tires, and boat trailer tires may dry rot long before the tread is worn. The two primary causes of environment degradation of tires are ultraviolet and ozone and both may impact vintage cars that are parked for extended periods of time. Ultraviolet rays damage any rubber that is left exposed to direct sunlight. Ozone will degrade any rubber that is exposed to the air.

It is important to remember to keep tires out of direct sunlight whenever possible. Also remember to keep the car in the garage, or at least covering the tires when it is stored outdoors, can help prevent ultraviolet damage. Move the vehicle periodically when it is in storage if possible. Flexing the tires during movement helps the protective waxes to work their way to the surface where they can protect against ozone. If there is any sign of dry rot or other damage to the tires, make sure to contact us as soon as you can.