How old can tires be? How long should I use one tire?
The older the tires, the greater the risk of damage and danger on the road. In turn, changing tires prematurely is simply a waste of money. In addition, it harms the environment, because, in place of a still good tire, you buy another one, which certainly does not reduce their production. So how do you determine the service life of your tires? And when is the best time to replace? Mateusz will answer all your questions in this article.
Tires - how to check the year of production?
Each car tire is marked with some symbols. Therefore, you need to know well what you are looking for. Information on the year of manufacture of the tires is right next to the letters DOT. The following sequence of characters and numbers indicates the factory code of the tire, the size code, and the week and year of production. The age of the tire may therefore be unintuitive to read, so we will now use an example. If there are signs DOT 3Y 1520 on the wheel, you can be sure that it was created in the Bridgestone factory in Poznań. In turn, the numbers 1520 mean that it was created in the 15th week of 2020, i.e. at the end of March. In this way, it can be determined that in August 2021 the age of the tire is approximately one and a half years.
Tire expiry date - does the tire have an expiry date?
Knowing how to check when tires were manufactured, one should ask the question: do they have an expiry date? Of course! It is even established by law. However, the validity of the tires relates to sales purposes only. According to the PNC 94300.7 standard adopted in Poland, tires can be put on sale no later than 36 months after production. The already mentioned DOT 3Y 1520 tire should therefore be withdrawn from sale by March 2023 at the latest. This also applies to used tires.
It does not mean, however, that it ceases to be useful after the indicated period. The service life of a tire and its expiry date are completely different issues. Much depends on the condition of the tires themselves. Winter and summer tires can be used for up to a decade if only a few conditions are met. They mainly concern proper care, driving culture (without sudden braking and exceeding the permitted speed limits) and avoiding difficult surfaces. In practice, extending the life of tires is not easy, but when used in urban conditions it certainly makes it easier.
How to judge when tires are worn out?
While the expiry date of tires is only a guideline for drivers, the technical condition assessment should already be obligatory. Worn tires simply increase the risk of accidents and vehicle failure. Fortunately, not all signs of a product deterioration are necessarily taking it out of service.
The TWI index is used to estimate tire wear. It is 1.6 mm. Manufacturers place elements on the tires that indicate that they are approaching a dangerous TWI level. On this basis, you can roughly tell how long the tires will last for. To measure the TWI indicator, you can use a standard caliper, coin, match or an electronic tire wear gauge, which can be purchased for several dozen zlotys.
When are tires fit to be thrown away?
Unfortunately, even high-quality tires have to be thrown away after some time. There are several reasons why an item needs to be replaced. The most important among them is the TWI indicator already mentioned. If the tire wears up to 1.6 mm, it stops fulfilling its function. However, it should be added that already at 3 mm it is worth considering replacement for your own safety.
Regardless of the TWI index and expiry date, it is assumed that after 10 years of use, the tires should be thrown away immediately. This is the maximum tire life it can achieve.
In addition, it is worth checking from time to time for deformation of the bead core, bulges on the sides of the tire or the appearance of stains and chafing inside. This also disqualifies the wheels from further use.
We hope that the above entry has cleared up any doubts about how often to change tires. Much depends on the constantly changing conditions and the experience of the driver. A skilled vehicle user will immediately notice that the tires are no longer fit for purpose and should be replaced. Nevertheless, thanks to the tips given, even novice drivers should not have any problems with it.