How to Read Tire Date Codesby Peter HallUpdated July 25, 2023
The condition of your car tires significantly impacts your vehicle's acceleration, braking, and cornering capabilities. Over time, the rubber of a tire degrades, and understanding this degradation process is essential for tire safety. In the United States, overseen by the National Highway Traffic Safety Administration (NHTSA), which is a part of the U.S. Department of Transportation (DOT), tires are given a date code which informs about the tire's age, making it crucial in knowing when to replace your old tires.
1. Locate the DOT code
Locate the DOT code on the tire using a flashlight. This code, also referred to as the tire identification number (TIN) or DOT number, usually comprises 10, 11, or 12 letters or numbers, starting with "DOT". It provides valuable information about the tire manufacturer, tire size, tire type, and the year and week of manufacture.
2. Note the last four digits
Note the last four digits of the DOT code, which represents the tire date codes. The final two digits specify the year of manufacture. For instance, if it reads 07, the tire was made in 2007. The two preceding digits, ranging from 01 to 52, signify the week of the year when the tire was produced.
If the DOT code on the outer sidewall of the tire is shorter than ten characters, you may need to remove the tire or get under the car. The full DOT code, including the manufacturer's code and plant code, is required to be on only one sidewall of each tire.
Both car tires and light truck tires from various manufacturers like Firestone, have these codes. Understanding these codes is crucial for determining the warranty of new tires and age of your tires. It's worth noting that the tire's age can influence factors like load index and ply.
The DOT code is a vital aspect of tire safety, regulated by the NHTSA. It is important for drivers to regularly check their tires' condition and to understand the significance of the numbers and letters DOT code to ensure they are driving on safe, adequately performing tires. Besides, if your vehicle is equipped with a Tire Pressure Monitoring System, make sure it is functioning well to maintain optimal tire performance and safety.
Tires made before January 1, 2000, had a three-digit date code. The final character was the last number of the year, while the two characters before that indicated the week of the year. There was no indication of the decade, so there is no way to tell whether a tire was made in 1997 or 1977.
Never get under a car supported only by a jack. The car could slip off the jack and injure you.
- Tires made before January 1, 2000, had a three-digit date code. The final character was the last number of the year, while the two characters before that indicated the week of the year. There was no indication of the decade, so there is no way to tell whether a tire was made in 1997 or 1977.
Things You'll Need
- Never get under a car supported only by a jack. The car could slip off the jack and injure you.
Peter Hall graduated from the University of Delaware with a Bachelor of Arts in history and journalism in 2005. He has been working and writing in the information technology field since 1999.