The final four digits, for any tire made since the year 2000, are the tire date code and represent the date of manufacture. The first two of these digits designates the week of the year the tires were made, and the final two digits are the last two digits of the year of manufacture. (For example, 1319 means the thirteenth week of 2019.)
In the case of the defective one, the last four digits are 4221 which is the 42nd week of 2021.
The tire isn’t past the expiration date of 6 years and is therefore a factory defect.
Hi guys, just happened to be passing by and saw this. Hope everyone is well!