Tires: manufacture dates, goodyear tires, 4 digits

Question
How do you read "dates of manufacture" on Firestone and Goodyear tires?

Answer
Bill,

ALL tires are required by law to have a DOT number (It's also called the serial number).  It is between 10 to 12 digits long and it is located near the letters "DOT" and it only needs to be on one side of the tire - and that side might be towards the inside of the vehicle.

The regulation that covers tires, say the first 2 digits are the plant of manufacture.  The second 2 digits are the tire size (in a code).  The next 3 or 4 are a code that describes the exact type of tire.

And the last 3 or 4 digits are the date code in a week/week/year or a week/week/year/year format.

Tire produced 1998 and earlier will have 3 digits and tires produced after 2000 will have 4 digits.  Between 1999 and 200 there was a transition from 3 digits to 4.

So if the last 3 digits are 236, the tire was produced the 23rd week of 1996 (or 1986 or 1976), and if the last 4 digits are 1807, the tire was produced the 18th week of 2007.