What Causes Tire Sidewall Weathering (aka Tire Dry Rot)?

The sidewall weathering that is visually evident on the tire occurs when the rubber compounds used to make the tire begin to break down.

Close up of weather cracking on a tire sidewall

As with most products, there is a natural degradation over time and exposure to adverse environmental conditions with the rubber compounds that make up a tire. Being exposed to high ozone concentrations in the atmosphere, climate changes, outside elements and misuse, these materials can begin wearing down faster, which may lead to cracking - a condition some may call “dry rotting.” Causes that lead to tires showing signs of early sidewall weathering can be attributed to five main areas:

  1. Excessive exposure to ultraviolet (UV) rays from sunlight
  2. Low inflation pressure in the tires
  3. Storing tires at extremely high temperatures
  4. Not using the tires due to lengthy storage of a vehicle or the tires themselves
  5. Storing tires near electric motors, battery chargers, generators, welding equipment, or other ozone-generating sources

What Does Sidewall Weathering Look Like in a Tire?

Closely inspected, properties of sidewall weathering will be easily noticeable and may take the following forms. After looking at your tires, if one of the following traits of sidewall weathering is evident in your vehicle’s tires, it is recommended to contact a Goodyear authorized service center or Goodyear dealer to have your tires inspected to gauge the severity of the issue.

  1. Breakable Appearance: The tire will appear harder than normal with the surface being brittle and touching the affected areas could cause pieces of the rubber to flake off.
    Close up of a brittle texture to a sidewall's surface area
  2. Cracking in the Tire’s Sidewall: Cracks on the sidewall of the tire will be noticeable and could extend to larger areas.
    Centerline cracks on tire
  3. Cracking in the Tire’s Tread Pattern: In the case of more advanced sidewall weathering, cracks on the tire’s tread may begin to appear.
    Close up of groove cracking in a tire's tread
  4. Discoloration: The color may begin to fade and may appear to be more of a gray tone.
    Close up of discoloration on a tire's sidewall

How to Keep Tires from Developing Dry Rot

Once deterioration becomes noticeable on tires, the best course of action is to replace the tires before additional damage can be done. Follow proper tire care and maintenance to help prolong the life of your tires from premature cracking.

Goodyear technician inspecting a tire with a customer

  1. Regular Inspections:

    Inspect both the sidewalls and tread of your tires monthly to monitor the overall condition, specifically looking for any cracks, discoloration, bulges, wear or additional unnatural blemish.

  2. Park out of the sunlight for extended periods of time:

    Too much exposure to UV rays from sunlight, especially in consistently warmer climates, is a leading cause of premature sidewall weathering. It’s recommended to park in more shaded areas if your vehicle will be exposed to excessive heat and sunlight. If you plan to park a vintage car or vehicle outside while storing, covering the vehicle and tires will help stave off UV rays.

  3. Cleaning and Protecting:

    The simple method is to clean the surface monthly with a washcloth using water and a mild dish soap. A water-based cleaner or solution such as this won’t harm your tires by adding any additional chemicals that could potentially impact the tire’s compounds and materials. After washing the tires with soap, give the tires a simple rinse with water.

  4. Avoid Harmful Products and Chemicals:

    If you are planning to use other tire protectants or cleaning products, read the product labels and be aware of what other chemicals are going on your tire. Stay away from using any cleaning products that are petroleum-based, as the products may degrade the rubber’s weathering agents that may lead to premature cracking.

  5. Proper Tire Inflation:

    One of the leading causes of tire failure is driving with underinflated tires. When tires are underinflated, there is increased wear on the tire tread, which generates excessive heat, and can result in severe cracking, component separation or a tire failure.

    Tires should be inflated at the proper levels recommended by your vehicle’s manufacturer and tire inflation pressure should be checked monthly. If cracking or sidewall weathering is evident in your tires, keeping the tires properly inflated may be more difficult not be possible as air loss may occur through the affected areas. Maintaining proper inflation pressure is the single most important thing you can do to promote tire durability and maximize tire life.

    Filling a tire with air using an air hose

     

  6. Overloading:

    Tires are specifically made to fit the vehicle and each tire has a recommended load capacity, which is the actual weight of the vehicle plus additional weight carried by that vehicle. Adding weight over that load capacity is considered “overloading”, and it will place too much stress on the tires. This additional weight to your tires may cause severe cracking or a potential tire failure. To learn more about your tire and vehicle load limits, consult your owner’s manual and learn more in our Tire Care & Maintenance Guide.

  7. Extended Parking Care:

    If a vehicle is planned to be stationary for an extended period, such as a vintage car, a trailer or recreational vehicle, it’s recommended to follow the steps below:

    1. If possible, store the vehicle in a manner that removes as much weight from the tires as possible (such as on jack stands).
    2. Store the vehicle out of direct sunlight.
    3. Cover the vehicle and tires to protect from any unnecessary UV rays.
    4. If the weight cannot be removed from the tires, move the vehicle at least every three months to shift the weight on the tires.
    5. Store the vehicle and tires in a clean and dry area away from any chemicals or large temperature shifts.
  8. Tire Storage Care:

    If long-term storage of winter or summer tires is planned, it’s recommended to follow proper guidelines. The ideal method to store tires would be to keep them mounted on their wheels and store on hooks through the rims themselves off the ground. Read more about how to store tires to help extend the life of your tires.

    Just as you invest in your vehicle, you invest in your tires. To help ward off the possibility of sidewall weathering in your tires, follow the suggestions above for proper care and maintenance. If cracks or noticeable sidewall weathering signs begin appearing, contact a local Goodyear location for a tire evaluation.

If there are signs of cracking in your tires, find a local Goodyear tire dealer near you today.