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Tires/Tire - DOT


I just purchased a tire for my trailer ST225/75D15. I would like to know the age of this tire.  The tire has DOT R2HH.  I've looked at several sites that explains how to read the "DOT" but I'm confused with the "DOT" that's on my tire.  Please help.

T Davis,

Everything you wanted to know about DOT Codes:

And then - you need to look on the other side of the tire.  What you have is a partial code - the plant and the size.  The full DOT code - including the date code - is only required on one side, and it appears that the tire has been mounted with that side in.


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Barry Smith


I have over 30 years experience in the design, manufacturing, and testing of tires. I have served as the technical advisor to the "800" number. I have authored or co-authored many publications - usually without credit. I can answer almost any technical question, but please don`t ask me to compare brands. I probably have prejudices because of my work experience.


Member SAE (Society of Automotive Engineers) Member Tire Society (Tire Technical Organization) SCCA Regional Competiton License holder Authored many training manuals on tires, their care and use.

SAE (Society of Automotive Engineers) SCCA (Sports Car Club of America) Tire Society

You may want to visit my web site:

I am a graduate of the University of Dayton, Dayton, OH - BME, 1971 I attended graduate school at the University of Akron - but did not complete my PhD - something I regret.

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