Interpretation ID: nht75-2.8

DATE: 09/19/75

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: Ben Perchik

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your letter of July 29, 1975, concerning tire identification markings, received by this agency on August 29, 1975.

I have attached two diagrams that illustrate the meaning of the tire code markings on new and retreaded tires. Immediately following "DOT" is a two- or three-letter code (marked in red on the diagrams) that indicates the manufacturer or retreader of the tire. I have also attached a list of the tire manufacturers and retreaders using each code. Following the manufacturer's code are two numbers representing the tire size (marked in blue on the diagrams). Next, some tires will have three letters or numbers which represent an optional tire type code mainly of use to the manufacturer (marked in yellow on the diagrams). The last three numbers represent the date of manufacture (marked in green on the diagrams).

I hope this information proves useful to you.