Did you know that rubber is an organic compound? Just like all organic compounds, rubber breaks down over time. This dramatically affects the usefulness of your tyres. As rubber breaks down, as it pertains to tyres, the rubber actually loses elasticity and becomes a lot more fragile. So, how do you know when a tyre is close to being reliable… or even dangerous to drive on.
What Happens When A Tyre Is Old.
As the composition of the tyre breaks down, the tire becomes more brittle and can lead to cracks and pieces of the tyre actually breaking off. As these cracks worsen in the tyre it can actually cause the fiber belts within the tyre to separate and break away.
In a study conducted by Safety Research & Strategies, INC. they found that in 2012 alone there were 252 accidents directly related to a tyre's age resulting in 233 deaths and 300 injuries. These could have been from de-treading, cracks, etc. When tyres age this dramatically they pose a huge threat to loss of control and rollover.
How Long Can A Tyre Last?
While there is no set “expiration age” that is officially dictated by any agency. Michelin was the first to suggest their tyres could last 10 years with yearly inspections after 5 years. However, most tyre manufacturers suggest that a tyre be decommissioned after 6 years, regardless of treadwear.
How Do We Know How Old A Tyre Is?
Just like anything else, there is an expiration date. Well… sorta. Ever since the year 2000 tyre manufacturers have been printing a DOT code that lets you know when the tyre is made. There will be a four-digit numerical code that will be on the sidewall. The first two digits let you know what week of the year the tyre was created, and the last two digits denote the year. So, if it says 3220 the tyre was created on the 32nd week of 2020.
Before 2000 the DOT code was a three-digit code that is preceded by a triangle. The first two digits denote the week, while the last digit says the year. For obvious reasons this wasn’t the most ideal way to let people know how old their tyres are. Either your tyre is too old to be safe, or pretty new. This leaves it on you to inspect the tire for imperfections to figure out the age. However, if you see this code GO GET NEW TyRES RIGHT NOW! That means your tyre is over 20 years old and is in no way safe to drive on. Seriously, stop reading this and go get new tyres.
The Word.
Tyres can be expensive and replacing tyres that still have tread can be a major bummer. However, it is a massive safety issue and is a pill that needs to be swallowed regardless of how tough it is. When it comes to safety, the only choice is the right one.
In 2013 the world learned the hard way how important tyre expiration and safety are, especially with performance tyres when Paul Walker lost control of Porshe Carrera GT. The world lost a talented actor who highlighted the world of motorsports that day. According to the California Highway Patrol Walker’s 9-year-old tyres may have been to blame.
Every tragedy caused by tyre age is preventable and can be used as a lesson to properly maintain and change out your tyres. If you have any questions about tyre expiration, check in with your tyre manufacturer’s specifications which should be accessible on their websites.