For years, people have relied on tread depth to determine when to replace a tire. If the tread passes the “coin test” they assume the tire still has life, regardless of how old it is, which can be a fatal mistake. Old tires are dangerous, regardless of tread depth.
Old tires have been the culprit in many fatal accidents The older a tire gets, the higher the risk of sudden and unexpected tread separation. The last four digits of the DOT code show how old the tire is. Ask our friendly team members to assist you with this.
It is worth noting the potential dangers of driving on aging tires — including those that have never spent a day on the road. The rubber compounds in a tire deteriorate with time, regardless of the condition of the tread.
For some people, old tires might never be an issue. If you drive a typical number of miles, somewhere around 10,000-15,000 kilometres annually, a tire’s tread will wear out in three to four years, long before the rubber compound does. But if you drive much less than that, or have a car that you only drive on weekends, aging tires could be an issue.
Similarly, if you are buying a used car, there’s a chance it may be riding on old tires. The age warning also applies to spare tires and seemingly new tires that have never been used but were produced years ago. Bring the car in for a pre-purchase inspection to us and we can help guide you with the right advice.
“If you take an unused rubber band that’s been sitting around and stretch it, you will start to see cracks in the rubber.” Cracks in a tire’s rubber begin to develop over time, appearing on the surface and inside the tire as well. This cracking can eventually cause the steel belts in the tread to separate from the rest of the tire. Improper maintenance and heat accelerate the process.
Every tire that’s on the road long enough will succumb to age. Tires that are rated for higher mileage have antiozonant chemical compounds built into the rubber that will slow the aging process, but nothing stops the effects of time on rubber.
What Happens to a Tire as It Ages?
Carmakers, tiremakers and rubber manufacturers differ in their opinions about the lifespan of a tire. The Rubber Manufacturers Association (USA) said there is no way to put a date on when a tire “expires” because such factors as heat, storage, underinflation and conditions of use can dramatically reduce the life of a tire. Here’s more on each of these factors:
Heat: It is well established that tires age more quickly in warmer climates. Environmental conditions, such as exposure to sunlight and coastal tropical climates, can hasten the aging process. People who live in the Northern Territory weather should keep this in mind when deciding whether they should retire a tire.
Storage: This applies to spare tires and tires that are sitting in a garage or shop. A tire that has not been mounted and is just sitting in a tire shop or your garage will age more slowly than one that has been put into service on a car. But it ages nonetheless.
Spares: They usually don’t see the light of day, but they’re still degrading with time. If the tire has been inflated and mounted on a wheel, it is considered to be “in service,” even if it’s never been used. And if a truck’s spare is mounted underneath the vehicle, it’s exposed to heat, dirt and weather — all reasons to plan on replacement.
Conditions of use: This refers to how the tire is treated. Is it properly inflated? Underinflation causes more tire wear. Has it hit the curb too many times? Has it ever been repaired for a puncture? Tires on a car that’s only driven on the weekends will age differently from those on a car that’s driven daily on the highway. All these factors contribute to how quickly or slowly a tire wears out.
Proper maintenance is the best thing a person can do to ensure a long tire life. It is important to maintain proper air pressure in tires, rotate them regularly and get routine inspections.
Make Sure You’re Getting a “Fresh” Tire
Just because a tire is unused doesn’t mean it’s new. In a number of instances, people have purchased “new” tires at retail stores only to find out that they were manufactured years earlier. In addition to having a shorter life on the road, a tire that’s supposedly new but is actually old may be past its warranty period.
If you buy tires and soon after discover that they’re really a few years old, you have the right to request newer ones. Any reputable store should be willing to make amends. But to save yourself the hassle, check the date before you buy.
Getting rid of an unused spare or a tire with plenty of tread may be the hardest thing for a thrifty owner to do. “Nobody’s going to take a tire that looks brand new and throw it out.” But if it’s old, that’s exactly what you should do.
Since there’s no proper consensus from the government or industry sources, we’ll just say that if your tire has plenty of tread left but you’re not sure on its age, it’s time to bring it to us and get it inspected for signs of aging.
Of all your vehicle’s components, tires have the greatest effect on the way it handles and brakes. So if the tire store recommends new tires at your five-year checkup, spend the money and don’t put it off. Your life could depend on it.