Might look to see if you can find a manufacturer's date on those. I thought the old design was replaced back in '05 or so... so might be you are on 10 year old tires.
Instructions
1
Look for the letters "DOT" to find the Department of Transportation number on the tire sidewall. The DOT tag indicates that the tire meets all federal standards.
2
Find the four numbers at the end of the code.
3
Look at the last two numbers to determine the year of manufacture. For example, if the DOT code ends in "2807," the "07" indicates that tire was made in 2007.
4
Look at the two numbers right before the numbers indicating the year to determine the week of manufacture. For example, if the DOT code ends in "2807," the "28" indicates that the tire was made in the 28th week of 2007.
5
Look at a calendar for the year and count the number of weeks to determine when your tire was made. In 2007, for example, the 28th week was July 8 to 14.
Read more: How to Determine the Age of BF Goodrich Tires | eHow
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