Are Your Tires Safe?
How We Make Tire Replacement Recommendations
According to the National Highway Traffic Safety Administration, there are at least 11,000 tire-related traffic accidents every year. How do you know when to change your tire? It’s not always easy to see. We utilize standards developed by the Tire Industry Association to keep you and your car safe. Not all shops, and not all tire stores use this industry criteria. At Convenience Auto Service, we are proud of the process we use to determine tire safety. No inspection can prevent all future tire issues. However, we’ve developed these procedures over our many years of being in business, and believe them to be more comprehensive, repeatable and above all, safer for you.
Tread depth is most important
Key criterions to determine the safety of your tire is the tire tread depth. At Convenience Auto Service, we utilize a mechanical tread depth gauge similar to the one pictured here:
Mechanical gauges provide a simple and repeatable indication of how deep the tread (or grooves) on the tire are. Tread depth is important because the grooves in the tire channel away water from the tire in summer months, and provide ‘bite’ in snow and ice during the winter. How much tread do you need to be safe? The Tire Industry Association (TIA) is a trade group that all major tire manufacturers belong to. The TIA sets standards and publishes guidelines for tire maintenance and replacement. The TIA recommends replacing any tire that is evenly worn with 2/32” of an inch (or less) of tread depth. We inspect multiple places around the circumference of the tire and record the minimum depth that we find. We measure from the top of the tread to the very bottom of the groove as shown in the picture. Taking multiple measurements provides the most accurate indication of wear. Not all shops and tire stores measure this way. If your vehicle has suspension or tire balance issues, it’s not unusual to see uneven wear – in that case, one portion of the tire may look fine, while another section is below the 2/32” standard. If any part of the tire is below the standard, we recommend replacement. The entire tire is only as good as its weakest point.
Most modern tires also have WEAR BAR INDICATORS. These are just small tabs of rubber that are molded into the tire grooves. When the existing tread becomes worn down to the top of the tread wear bar on any section of the tire, that tire should be replaced. This is a simple visual indication that you can even perform yourself. We look at multiple places across the face of the tire and around the entire circumference. If there is ANY place where the tread is worn down to the wear bar, we recommend replacement.
In any case, we report to you what we observe and let you make the final determination. We want you to know how safe your tires are whether you purchase tires from us or from someone else.
Tire date codes
Did you know your tire has a manufacturing date code? Tire Age is the most overlooked reason tires may become worn out. Usually, most tire treads will wear down long before any expiration date. The National Highway Safety Administration and the Tire Industry Association recommend replacing tires when they exceed 6-10 years old, regardless of tread wear. Weather conditions, thermal cycles, and the natural breakdown of rubber and other materials in the tire degrade performance characteristics over time, with potentially serious consequences. The date your tire was manufactured can be determined by checking at the Department of Transportation Tire Identification Number (TIN) stamped on the sidewall of every modern tire. The last four digits of the TIN will indicate the week and the year the tire was made.
In the case of this photo, 1309 represents that the tire was made the on the 13th week of 2009 (or March 23rd- 29th). This means the expiration date would be the week of March 23, 2015. It is important to also check the age of your tires, because even though you may have just purchased them from a tire store, the tire may have sat in a warehouse for a long period of time prior to your purchase.
We are proud of the process that we’ve developed to determine and report tire wear. We believe that our process is both repeatable and rooted in industry accepted best practices. Please remember that not all places that sell tires (especially tire stores) do as rigorous an inspection as we do. We make the recommendation and let you decide! It’s just another way we work hard to keep you and your car safe.