Customer Information and Reporting Safety Defects; Tire Information (U.S.A.)- Page 540

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Customer Information and Reporting Safety Defects

Tire Information (U.S.A.)

  H

    “H” is the speed rating. The speed rating denotes the maximum speed for which the use of 
the tire is rated.

 Letter  Rating 

 Speed  Rating 

 Q 

 99  mph 

 R 

 106  mph 

 S 

 112  mph 

 T 

 118  mph 

 U 

 124  mph 

 H 

 130  mph 

 V 

 149  mph 

 W 

 168 

*

   mph 

 Y 

 186 

*

   mph 

*

  For tires with a maximum speed capability over 149 mph, tire manufacturers sometimes 

use the letters ZR. For tires with a maximum speed capability over 186 mph, tire 
manufacturers always use the letters ZR.

  M    S or M/S: Mud and Snow

    AT:  All  Terrain.
  AS:  All  Season.  The  “M S” or “M/S” indicates that the tire has some functional use in mud 
and snow.

  U.S.  DOT  Tire  Identifi cation Number (TIN)

    This begins with the letters “DOT” which indicates the tire meets all federal standards. The 
next two numbers or letters are the plant code where it was manufactured, and the last four 
numbers represent the week and year the tire was manufactured. For example, the numbers 
457 means the 45st week of 1997. After 2000 the numbers go to four digits. For example, 
the number 2102 means the 21th week of 2002. The other numbers are marketing codes 
used at the manufacturer's discretion. This information is used to contact consumers if a tire 
defect requires a recall.

  Tire Ply Composition and Materials Used

    The number of plies indicates the number of layers of rubber-coated fabric in the tire. 
In general, the greater the number of plies, the more weight a tire can support. Tire 
manufacturers also must indicate the tire materials, which include steel, nylon, polyester, 
and other.

  Maximum  Load  Rating

    This number indicates the maximum load in kilograms and pounds that can be carried by the 
tire.