How do I Tell the Age of Uniroyal Tires?by Tim Plaehn
The U.S. Department of Transportation dictates what information must be provided on the sidewall of a tire. Tire data includes the tire size, load capacity and speed rating. Further information printed on a tire show when and where the Uniroyal tire was manufactured. The information is coded, but easy to decipher if you know how the code works.
Find the DOT number on the sidewall of the Uniroyal tire. The number starts with DOT and is followed by a series of letters and numbers. If the DOT number is just a few characters long, you are looking at the back of the tire. The full DOT number is on the front if the tire and will have about 12 characters.
Write down the last four characters of the DOT number. They will all be numbers, no letters.
Decode the tire manufacture date using the four-digit number. The first two digits are the week of the year the tire was manufactured and the second two digits are the year of manufacture. For example, if the last four of the DOT number is 4008, the tire was manufactured in the 40th week of 2008.
Subtract the date of manufacture from the current date to get the age of the tire. If the tire was manufactured in week 40 of 2008, the tire was built in September. If it is August of 2010, the tire is one year and 11 months old.
- The four-digit manufacture date is for tires produced in the year 2000 or later. In prior years, the date indicator was just three numbers. The numbers 368 would mean the tire was manufactured in the 36th week of 1998 or 1988.
- Divide the number of weeks by 4.3 to get the numeric month of manufacture.
- The factory warranty on most tires is good for five or six years after the date of manufacture.
- Tires more than six years old should not be used. Older tires can weaken and rot without visible damage.
Tim Plaehn has been writing financial, investment and trading articles and blogs since 2007. His work has appeared online at Seeking Alpha, Marketwatch.com and various other websites. Plaehn has a bachelor's degree in mathematics from the U.S. Air Force Academy.