Tire maintenance is an essential part of owning a vehicle in todays day and age. But sometimes you can wonder if you’re receiving the best performance out of your vehicle. Knowing how old your tires are and in what condition they’re in is a good way to keep your vehicle handling the best and keeping yourself and others safe as well!

WHAT IS A DOT?

The Department of Transportation and safety markings provide information about your tire’s production and its compatibility with federal regulations. You will see these figures stamped on the sidewall in a sequence that looks similar to the sizing code. The DOT Date Code and safety markings will look like this:

 

The first step in finding out your tire’s age is locating the DOT Date Code on the tire. Not only can it tell you the timeframe your tires were manufactured, but who manufactured it, where it was made, as well as indicating that the tire has met or exceeded the Department of Transportation’s testing and NHTSA manufacturer requirements for on-road use. Without it, tires should not be legally driven on US public roads.

PLANT CODE

The plant code appears as the two letters after “DOT.” These characters identify the tire’s manufacturer and site of creation. In our example, the plant code is represented by the letters “CC”.

MANUFACTURER TIRE SIZE

After the plant code, you will find two characters that express the tire size in a code determined by the manufacturer. The code “9L” is used in our tire.

BRAND SPECIFIC CHARACTERISTICS

The first three characters after the dash represents brand characteristics in a code also determined by the manufacturer. The plant code, tire size, and brand characteristics are intended for the manufacturer’s internal use. For example, the letters in our code is “XYZ”.

DATE OF MANUFACTURING

Finally, after the brand characteristics, there are four numbers representing the tire’s date of creation. The first two numbers in this sequence tell you the tire’s manufactured week. The manufactured week identifies which week of the year the tire was made in. Our example tire lists 10 as it’s manufactured week, so it was produced in the 10th week of the year. The year of manufacturing is represented by the last two of the four digits. The manufactured year identifies the year the tire was produced. Here, it says the year of manufacturing code is “16”. When you combine the manufacture week and year, you can deduce when the tire was made. Our example tire lists “10” as its manufactured week, and “16” as its manufactured year. From this we now know it was made during the 10th week of 2016.

HOW OLD IS CONSIDERED TOO OLD?

A general rule of thumb from various tire manufacturers around the world is that tires have a general service life of around six to ten years. As technology changes however, there are more materials, and combinations of compounds that can extend tire life and extend wear. When your tires approach seven years of age, we recommend that you consider replacing them. Even if the tires look new, it is best to have them inspected by a professional tire installer, so they can properly advise on the safety of the tires moving forward. Spare tires should be checked and replaced as well, if necessary.

No matter how old the tires are when you buy them, the most important rule of tire safety is regular maintenance and inspection.