Both tire and auto manufacturers recommend frequently checking your tires for signs of irregular wear or any other damage that could cause a dangerous tire failure. While signs of shallow cracking on the sidewall rubber or minor irregular wear are of concern, the presence of a bubble in the tire sidewall is a major safety concern that needs to be addressed immediately. A bubble in the sidewall of the tire indicates that the inner liner has been damaged to the point that it's allowing air to escape. Also, only the thin (nylon or polyester) sidewall plies are keeping the tire from a blowout.
Bubbles or bulges in the sidewall are normally the result of the tire's inner liner being damaged from an impact that creates a small hole or tear and compromises the strength of the sidewall plies. In most cases, the impact that caused the damage was not severe enough to be noticed by the driver, yet it was strong enough to damage the tire. Impacts with curbs, potholes, railroad crossings or debris in the road are the most common culprits. On occasion, a sidewall bubble can be caused not by an impact, but a structural failure of the tire. In these limited occurrences, the tire can be replaced with a prorated discount or refunded by the tire manufacturer's warranty. Regardless of the cause of the damage, a bulge in the sidewall is a blowout waiting to happen at any moment and needs to be addressed.
An authorized distributor of the tire can inspect the tire for possible damage that would be covered under the manufacturer's warranty. You can also call the tire manufacturer directly or contact us for assistance with your Tire Rack order. Our Recommended Installers are also able to assist with the evaluation of a tire.
For more information on tire damage, read "Sidewall Indentations, Undulations and Protrusions."