All you have to know about the DOT

All you have to know about the DOT

Why should I know what it is? If I buy tires which are older than 2 years, is it unsafe? If I don't use them that much, should I still change my tires? When?

All tires manufactured or imported into Canada must have an identification number that includes the date of manufacture. This date is identifiable in the same way as in the USA. Tires manufactured in or imported into the United States are all marked "DOT" on their side - for Department of Transportation. This is usually followed by 4 to 8 characters, then four digits. These numbers indicate the date of manufacture. For example, 3615 means that the tire was manufactured in the 36th week of 2015. An older tire may have only three digits. If you have tires with the numbers 239 for example, it means they were manufactured the 23rd week of 1999. If so, it's really time to change them. 

First you must know that the rubber used for the conception of tires has improved significantly and are no longer quite influenced by the weight of time as in previous gums. The tire itself will not be less efficient if it is stored in optimal conditions. The tire should be stored in the dark and not on the cement. If it has been stored correctly, an unused tire is considered new until 5 years after its date of manufacture

Curiously, there is no legal age limit for a tire. Industrialists, retailers and governments all refer to this average six-year life span. There are too many factors involved in determining the legal age of a tire. Its duration depends for example on exposure to sunlight in a warehouse or on the edge of the sidewalk. Under the hot rays of the sun a tire continues to cook. An underinflated tire also creates significant heat. The frequency of driving, the composition and quality of the tire, as well as the maintenance of the vehicle also determine its service life. 

If you do not roll a lot your tires, it get older anyway, aging depends a lot on storage conditions. For a car that sleeps outside, exposed to weather and UV, the life of a tire does not exceed five years. On the other hand, when the car is parked in a constant temperature garage, the longevity of your tires can double. In any case, from five years of age, the condition of your tires should be checked regularly. The tire is made of rubber, it is a material that tends to harden over time and deteriorate. Even if it does not have an expiry date, the lifespan of a tire is on average 5 to 10 years. It varies according to your driving style, maintenance that you bring: inflating, storage ... From 5 years, you must regularly check their condition. Beyond 10 years, their grip on the ground is no longer guaranteed it is better to change them for your safety. 

According to tire professionals, a new factory tire should not be put on a vehicle "after six years of storage or after 10 years of use and storage". Be reassured "There is currently no data linking a collision and a tire defect due to age at the time of sale by the manufacturer, or evidence that establishing a expiry date on new tires would reduce collision rate on the road "according to Transport Canada. 

If you want to make sure you drive safely on good tires, check the date of manufacture. 

The date of manufacture of my tires is important, but the way they are stored is just as important. 

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