If you think that all new purchased tires are in fact new better look again. Some of the tires purchased as new are in fact tires that should not be sold as new because of their age.  Tires that are six years old or older should not even be used on the road because of deterioration due to age.  The Department of Transportation warns of older new tires being sold when they should not be on the road.

How to tell the age of your tires no matter when you purchased them.  Here are the meanings of the DOT Codes.  First check for the DOT letters on the sidewall of the tire this means that the tire meets DOT safety standards.  The next letters after the DOT are the code for the tire plant.  The next numbers are the tire size code.  The next four letters are the tire brand code.  The next four numbers are the date code or when the tire was made. 

These numbers are the week of the year and the year code for when the tire was made.  The last four numbers in this example are 4202 so this tire was made the 42nd week of 2002.  A tire with the numbers 3306 was made the 33rd week of 2006.   Tires made in the 90's had only three numbers such as 403 so this tire was made the 40th week of 1993.

Be sure and take a look at any new tire that you purchase before they are installed on your vehicle.  Be sure to check all of the tires not just one.  I purchased a set of four new tires at a major tire company.   I got in my pickup and drove to a lube station to have the oil changed and when I got out of the truck I noticed that the tire on the left rear had mud on it.  Now this was back early in the summer and it had not rained in six months.  As I looked at the tire it appeared to be almost new but it was seven years old.

When I went back to the tire store and complained and they could not understand why I was a little upset. I called the home office and they had the same approach.  I did get the tire replaced but that was not the point.  If I had not noticed the tire and had a blow out on that tire it could have been serious. I found out that it was a spare on a customer's pickup that they had sold a new set and put the tire in stock as new. The date number on the tires that I now have on my pickup is 4007, so they were built the 40th week of 2007.  Be sure and check tire age on all vehicles that you have on the road, look for age wear etc.