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Tire Safety & Date Codes

November 13, 2009 | Safety & Driving

By Barry Lee Brisco

If your tires are over 9 years old, replace them! Old tires can look essentially new if the car is kept indoors and driven infrequently. But 10-year old tires with only 1,000 miles on them are more dangerous than 2-year old tires with 20,000 miles on them. To determine the age of your tires, look at the date code on their sidewall. Before 2000, the date code had three digits. Since 2000, it has had four. The date code is found in a marking that follows one of the following formats:

From 2000 on: DOT XXXX XXX XXXX
Last four digits: date code (week / year of manufacture)
First two characters: manufacturing plant identification mark
The other characters are left at the manufacturer's discretion.

Before 2000: DOT XXXX XXXX XXX (older three-digit date code format)
Last three digits: date code (two for the week / one for the year)
First two characters: manufacturing plant identification mark
The other characters are left at the manufacturer's discretion.

Example: DOT P1RW B4LR 109: This particular tire was made on the 10th week of 1989 or 1999.

Example: DOT E4 508: This tire was made on the 50th week of either 1988 or 1998.

Example: FHTB A1M x 071: This tire was made on the 7th week of 1981 or 1991.

NOTE: Bob Campbell informs us that "The three digit date code in the 1990's had a small triangle next to the three digits. If it is three digits and no triangle, it is from the 1980's."

If you cannot find a date code, don't just hope for the best and keep using them, buy new tires!

I once purchased a 356 with tires that looked nearly new. They had almost no tread wear, and only a few tiny cracks in the sidewalls. Checking the date code, I was astonished to discover that they were over 10 years old. So, if your tires are over 9 years old, replace them!

Tires are cheap...life is priceless.


Other 356 Registry Articles on Tires
Calculating Tire Dimensions & Comparative Tire Sizes
Tire Pressures for the 356
Tires With Tubes – Original Yes, Needed? No
Wheel Weights

Tire Resources Online
www.tireindustry.org
http://www.apa.ca

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