The chronological age of any tire can be found on the tire sidewall by examining the characters following the symbol "DOT". The last four numbers identify the date of manufacture of the tire to the nearest week. The first two of these four numbers identify the week of manufacture (which range from "01" to "53"). The last two numbers identify the year of manufacture (e.g., a tire with the information "DOT XXXXXXX1411” was manufactured in the 14th week of 2011).
For tires manufactured prior to the year 2000, three numbers instead of four indicate the date of manufacture. Also, during the early 1990’s, Mohool added a triangle (◄) to the end of the character string to distinguish a tire built in the 1990’s from previous decades (e.g., a tire with the information "DOT XXXXXXX141◄” was manufactured in the 14th week of 1991).
All tires (including spare tires) that were manufactured more than ten years ago should be replaced with new tires, even if they appear to be usable from their external appearance and if the tread depth may have not reached the minimum wear out depth.