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Interpretation ID: GF000492

    Mr. Guy S. Edington
    Vice President, Technology
    Kumho America Technical Center
    3500 Embassy Parkway, Suite 150
    Akron, OH 44333


    Dear Mr. Edington:

    This is in response to your January 16, 2006, letter and subsequent phone conversation with George Feygin of my staff regarding certain requirements in Federal motor vehicle safety standard (FMVSS) No. 119, "New pneumatic tires for vehicles other than passenger cars."As Mr. Feygin explained to you, this letter is limited to the discussion of the current regulations and does not address suggestions you made concerning how you believe certain tires should be tested.

    The National Highway Traffic Safety Administration (NHTSA) issues FMVSSs applicable to new vehicles and equipment, including tires. NHTSA does not provide approvals of motor vehicles or motor vehicle equipment. Under 49 U.S.C. Chapter 301, manufacturers are required to certify that their vehicles and equipment meet applicable requirements. Thus, the tire manufacturer is responsible for self-certifying its product.

    S6.2 of FMVSS No. 119 specifies certain tire strength requirements that tires must meet when tested according to the procedure specified in S7.3. As a part of this procedure, a cylindrical steel plunger is forced perpendicularly into a raised tread element as near as possible to the centerline of the tread, at a rate of 2 inches per minute, until the tire breaks or the plunger is stopped by the rim. The diameter of the plunger depends on the diameter of the rim and is specified in Table I. You ask what diameter plunger is used to test tubeless 17.5 diameter code "medium duty truck" tires.

    Table I of FMVSS No. 119 specifies that for tubeless tires with a diameter code of 17.5 or smaller, a plunger with a diameter of inches (19.05 mm) is used. Table I does not differentiate between different categories of 17.5 diameter code tires and does not provide for use of different plunger diameters for any 17.5 diameter code tires.

    I hope you find this information helpful. If you have further questions, you may contact Mr. George Feygin of my staff at (202) 366-2992.

    Sincerely,

    Stephen P. Wood
    Acting Chief Counsel

    ref:119
    d.4/7/06