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Interpretation ID: nht76-5.17

DATE: 11/10/76

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: E. D. Etnyre & Company

TITLE: FMVSR INTERPRETATION

TEXT: This is in belated response to your letters of June 22, 1976, concerning the availability of NHTSA interpretation letters and the assignment by vehicle manufacturers of Gross Axle Weight Ratings.

Letters written by this agency that interpret the Federal Motor Vehicle Safety Standards or accompanying regulations are regularly compiled by standard or regulation number and placed in a public file (the "redbooks") in the Docket Section at Room 5108, 400 Seventh Street, S.W., Washington, D.C. Copies of these letters are distributed informally by various trade associations, as you have noted. However, there is currently no subscription service available directly from the NHTSA. I recommend that you periodically (bimonthly, perhaps) telephone the Docket Section (202 426-2768) to find out whether entries have recently been made in the Redbooks under the standards and regulations that are of particular concern to you.

You have also asked several questions concerning the relationship between an axle's Gross Axle Weight Pating (GAWR) and the overloading of that axle when the vehicle is in use. GAWR is defined in 49 CFR 571.3 as

the value specified by the vehicle manufacturer as the load-carrying capacity of a single axle system, as measured at the tire-ground interfaces.

It is thus a rating assigned by the manufacturer at the time of manufacture. A vehicle whose axle weight ratings are likely to be exceeded under the manufacturer's intended or reasonably forseeable conditions of usage would probably be considered to contain a safety-related defect. Such a vehicle would be subject to the notification and remedy provisions of the National Traffic and Motor Vehicle Safety Act of 1966, as amended (15 U.S.C. 1392 et seq.).

We cannot prescribe specific steps that a vehicle manufacturer must take to ensure that a GAWR would not be found so low that it would be a safety-related defect. For example, if a warning in the owner's manual against loading in a certain manner is likely to be ignored, then such a warning would not, by itself, be sufficient. The NHTSA expects the vehicle manufacturer to take reasonable steps, short of retraining from production, to minimize the likelihood of vehicle misuse through overloading.

SINCERELY,

E.D. ETNYRE & CO.

June 22, 1976

U.S. Department of Transportation Legal Counsel - NHTSA This matter refers to Part 567 "Certification" and Part 568 "Vehicles Manufactured in Two or more Stages" of 49CFR.

Many of the interpretations and comments dealing with "rated loads" refer to the circumstance of exceeding the Gross Vehicle Weight Rating (GVWR). However, the certification label also requires that the Gross Axle Weight Rating (GAWR) also be noted. We have not as yet seen any question or interpretation dealing with the matter of overload on an axle. Our questions then are as follows.

1. Assume a tank type motor vehicle; which when loaded full to its rated cargo load; expressed as a volume of a specific commodity. (i.e., water); does not exceed the GVWR rating but the load is distributed such that a GAWR is exceeded. Is this a violation of the regulations?

2. Assume the same type vehicle loaded with a material whose specific weight varies over a limited range but does have an average acceptable value for general use (i.e. asphalt). If a GAWR is exceeded is this a violation of the regulations?

3. Assume a vehicle as in paragraph 2, constructed of compartments for variable commodities and designed for a specific loading arrangement. If the loading arrangement is not followed by the user and the GAWR is exceeded but not the GVWR, is the manufacturer liable?

4. Assume a vehicle as in paragraph 1, which is loaded full by the user with a material heavier than specified and designed for by the manufacturer and both the GVWR and GAWR are exceeded, is the manufacturer liable?

5. If a volumetric load of specific weight is considered by the manufacturer in rating the vehicle, what steps are necessary to protect the manufacturer from alleged violations of rating if other commodities are carried?

Jackson Decker Chief Product Engineer

E.D. ETNYRE & CO.

June 22, 1976

U.S. Department of Transportation Legal Counsel - NHTSA

We have become aware of the process whereby interpretation to paragraphs of Parts of 49CFR (particularly Parts 567, 568 and 571) are distributed on an informal basis through various trade associations. We further note that they apparently are carried in your files under the designation of "N40-30".

Since our activities are not completely served by any one particular association and we are not prepared to join a multitude of associations, is there a compilation of interpretations which are available from NHTSA on a regular or subscription basis? If there is such a service we would appreciate hearing about it. If not, how do we assure ourselves that interpretations which are being made on matters of common concern are made available to us so that we can comply with these interpretations?

Jackson Decker Chief Product Engineer