Most motorists are aware of the dangers surrounding tires that are poorly inflated or flat, but many aren't aware of the hidden dangers of an old or worn tire. The danger doesn't immediately present itself making motorists more inclined to keep their tires. The older a tire is, the higher a risk for the tread to separate unexpectedly. Often, during the worst of times resulting in auto accidents, which may involve injuries or even death. For years, it was common knowledge for people to buy tires based on the tread usage. Many diagrams and pictures can be found in vehicle maintenance books as well as the Internet depicting the use of a penny to determine the condition of the tire itself. Unfortunately, few realize how the structural components of a tire will deteriorate over time regardless of outside appearances. An old tire, regardless of how new it looks can potentially pose a safety hazard. For some motorists, they may never have to worry about old tires. If you drive between 12,000 and 15,000 miles annually, the tread on the tires will wear out within three to four years with regular driving on paved roads. Surprisingly though, if you get little use from your vehicle, you may be at more of a risk from aging tires compared to people who use their vehicles regularly. The risk is also exponentially higher for spare tires that haven't been used but are still aged. How A Tire Ages An old tire is a lot like an old rubber band. A rubber band that has been exposed to the elements or that has been used frequently will show visible cracks when stretched out. The rubber band concept can be used to relate to the aged tire. As a tire is put onto a vehicle and driven, the elements and age will work against the materials of the tire to cause cracks in the rubber to form. The cracks may not be visible to the naked eye; in fact, the cracks may form only inside the tire. Eventually over time, the cracking will cause the steel treads to separate from the rubber components of the tire. Regardless of how long a tire is on the road; the tire will eventually age over time. While shopping for new tires, you may have seen or heard of tires built to withstand higher mileage. The difference between these tires and regular tires is the antiozonant chemical used while manufacturing the rubber to make the tires. While these advances in tire manufacturing may allow motorists to get more miles out of their tires, these special tires are still at risk. How Long Can a Tire Be Used? If you ask auto manufacturers, tire manufacturers and even rubber manufacturers the average lifespan of a tire, they'll all give you different opinions. The National Highway Traffic Safety Administration doesn't have any specific recommendations except to check with the tire manufacturers themselves. Auto Manufacturers such as Nissan and Mercedes-Benz frequently suggests to auto buyers to replace their tires every six years. Tire manufacturers such as Continental and Michelin suggest tire replacement every 10 years or so, as long as the motorist has their tires inspected after the 5th year of use. Factors That May Increase the Wear and Tear On TiresHeat: Most tires will age quicker in warmer climates compared to colder climates. Constant exposure to sunlight and coastal elements may speed the process up. Therefore, people who live on the coast should keep these facts in mind when determining when to replace their tires. Storage: Any tire that sits in a garage or shop unused for an unspecific amount of time will age faster compared to a tire that is on a frequently used vehicle. One thing to keep in mind: If a tire has been mounted on a wheel, it is considered as "in-service", meaning it should be treated as if it was mounted on a vehicle. A tire not mounted on a wheel will age slower. Use and Abuse: The way a tire has been treated during use is a more accurate assessment on determining how long your tires will last. If you've abused your tires, they will age faster. Abuse may include running into curbs, driving regularly on highways, etc. If in doubt of the safety of your tires, have them inspected and rotated regularly by bringing your car into our shop. How Old Is My Tire? Upon inspection of a tire, a motorist may be confused by all the letters and numbers stamped on the sidewall of the tire. These are not modern hieroglyphics. They can be used to help determine the age of the tire. A much more detailed article on reading tires can be found online, but for the sake of simplicity we'll quickly summarize how you can use these numbers and letters to determine how old the tire is yourself. Fortunately, all you need for this exercise is the U.S. Department of Transportation Number or DOT number. Tires manufactured after 2,000 have a four-digit DOT code. The first digits of the code will tell you the week when the tire was manufactured. The second two signify the year. For example: A DOT code of 1109 tells us the tire was manufactured in the 11th week of 2009. If your DOT code is a three-digit code, it may be trickier to determine the exact date. DOT codes were not originally used for consumers to determine the age of their tires, they were printed on tires to help NHTSA recall tires that were unsafe for use. Some DOT codes are not immediately visible and may require a technician to locate them. The code may be easy to find once the car is raised on a lift. Keep this in mind the next time your vehicle is due for a tire rotation. Avoid Buying Used Tires Despite how tempting it may be to buy old tires for cheap, avoid doing so. It's difficult to determine how much abuse the tire has been through, which could endanger your life, the lives of passengers, and other motorists. If there's any doubt, give us call today and schedule a free tire inspection. We'll put your mind at ease!