As a complimentary service to you, the Tire Identification Codes for the
tires you purchased will be automatically registered with the
Department of Transportation (DOT).

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Dibs on your Cool Ranch Doritos

Federal law requires tire manufacturers to provide standardized information permanently branded on the sidewalls of all tires sold in the United States. This includes information about the tire’s basic characteristics, capacities and construction, as well as its U.S. Department of Transportation (DOT) Tire Identification Number used for safety standard certification and in case of a recall.

Current regulations require that Tire Identification Numbers begin with the letters "DOT," followed by ten, eleven or twelve characters (see photo below) that can be used to identify the manufacturing location, tire size and manufacturer's specifications, along with the week and year the tire was manufactured. So while DOT Tire identification Numbers are commonly but erroneously referred to as the tire’s serial number, unlike the serial numbers used on most other consumer goods that identify one specific item, Tire Identification Numbers actually identify production batches.

Because not all tires are intended to be imported and sold in the United States, many tires are developed and produced without being tested by their manufacturer to confirm they meet all U.S. Federal Motor Vehicle Safety Standards (FMVSS). Without conducting the tests and certifying these tires meet U.S. requirements, these tires are not allowed to be branded “DOT” (shown below) and cannot be legally driven in the United States.

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The purchase is registered for recall purposes, so that in the event of a recall/systemic problem they know who to contact.

Production codes/date of manufacture as in the last 4 digits tell you the week and year of manufacture. 2513 would be the 25th week of 2013 for example.

All tires approved for highway use in the U.S. have a DOT number molded into the lower sidewall of the tire immediately above the bead that identifies the manufacturer, plant, and date of manufacture.

Registration of dot's has a very low compliance rate.