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Interpretation ID: GF008935

    Ms. Dana Roeling
    Executive Director
    National Mobility Equipment Dealers Association
    3327 W. Bearss Avenue
    Tampa, FL 33618


    Dear Ms. Roeling:

    This is in response to your letter concerning legal responsibilities of vehicle modifiers (i.e., entities that modify motor vehicles after the first retail sale) with respect to the requirements of S4.3 of Federal Motor Vehicle Safety Standard (FMVSS) No. 110, Tire selection and rims for motor vehicles with a GVWR of 4,536 kilograms (10,000 pounds) or less. Specifically, you ask whether vehicle modifiers are obligated to replace the tire safety information placard required by S4.3, if the relevant information on the placard becomes inaccurate as a consequence of their actions. As explained below, the answer is no.

    By way of background, S4.3 of FMVSS No. 110 requires that vehicles with a GVWR of 10,000 pounds or less contain a placard showing certain critical tire safety information, including but not limited to, the vehicle capacity weight, the recommended inflation pressure, and the tire size designation. This information enables consumers to ascertain the cargo carrying limitations of their vehicles, and to properly inflate their tires. It also enables consumers to purchase correct size replacement tires.

    49 U.S.C. 30122 prohibits manufacturers, distributors, dealers, or motor vehicle repair businesses from "making inoperative, in whole or in part" any part of a device or element of design installed on or in a motor vehicle in compliance with an applicable safety standard.

    In your letter, you ask whether it would be a violation of the 30122 make inoperative provision if modifiers changed the vehicles such that the information of the tire placard is no longer accurate, but do not update the tire placard.

    In evaluating this question, we have focused on the language of S4.3 of FMVSS No. 110. One of the items of safety information required by that section is identified in paragraph (d), which reads as follows:

    "Tire size designation, indicated by the headings "size" or "original tire size" or "original size," and "spare tire" or "spare," for the tires installed at the time of the first purchase for purposes other than resale. For full size spare tires, the statement "see above" may, at the manufacturer's option replace the tire size designation. If no spare tire is provided, the word "none" must replace the tire size designation;" [Emphasis added]

    Thus, the requirement for one of the critical items of safety information to be provided on the tire placard is specifically expressed in terms of the "tires installed at the time of first purchase for purposes other than resale." We also note that there is a relationship between a number of the items required to be specified on the tire placard.

    We observe that regardless of what changes a modifier may make to a vehicle, it does not change the size of the tires that were installed at the time of the first purchase for purposes other than resale (the information S4.3 of FMVSS 110 requires to be on the placard).Given this, and recognizing the relationship between a number of the items required to be specified on the tire placard, it is our opinion that it would not be a violation of the 30122 make inoperative provision, with respect to S4.3 of FMVSS 110, if modifiers change the vehicles tire size, cold inflation pressure, and/or cargo capacity rating but do not update the tire placard.

    We note that while our regulations do not require changes to the tire safety information placard if the changes to the vehicle occur after it is first sold for purposes other than resale, the potential inconsistency between the information on the placard and the actual vehicle could in some cases be misleading and dangerous to vehicle operators. Specifically, relying on what has become inaccurate information, vehicle operators could over-inflate or under-inflate their tires, thereby creating a safety hazard. Also, vehicle operators could overload their vehicles, which also would create a safety hazard. Finally, vehicle operators could end up purchasing incorrect replacement tires (e.g., original tire size not appropriate for aftermarket rim), erroneously relying on the placard that is no longer accurate.

    In light of these concerns and consistent with previous interpretation letters concerning post-sale modifications relating to a vehicles Gross Vehicle Weight Rating (May 24, 1993, letter to Mr. John Paul Barber, Esq., and April 2, 1997, letter to Mr. James Baker), we would urge a party which modifies a used vehicle so that the tire safety information is no longer accurate to either add a new label to the vehicle which indicates the correct tire safety information or add a warning label (preferably proximate to the placard) indicating that the tire safety information placard is no longer accurate.

    In your letter, you ask several questions highlighting the potential difficulties faced by vehicle modifiers attempting to ascertain accurate tire safety information, especially in situations where a vehicle has already undergone changes after the first sale. For example, the vehicle being modified could have tires that are different in size and recommended inflation pressure from those originally installed on the vehicle, and thus the information on the tire safety placard is already wrong when the vehicle arrives for modifications. As discussed in the previous paragraph, we would encourage vehicle modifiers to either affix a correct label or affix a warning indicating that the tire safety information placard is no longer accurate. In situations when the accurate tire safety information is difficult to ascertain, we encourage the latter option of a warning label.

    You also ask a question regarding S4.3.2 of FMVSS No. 110. That section applies to vehicles altered prior to first retail sale and specifically requires that a new tire information placard replace the original placard if the previously certified vehicle has been altered such that the information on the existing placard is no longer valid. We caution that this interpretation applies only to modifications occurring after the first retail sale and does not concern alterers.

    Finally, we note that with respect to modifications of vehicles to accommodate individuals with disabilities, 49 CFR 595.7(e)(5) requires modifiers to provide the vehicle owner with a document that indicates a reduction in the load carrying capacity of more than 100 kg (220 lb) after the modifications are completed.

    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:110
    d.4/7/06