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Interpretation ID: nht78-3.33

DATE: 04/05/78

FROM: FRANK BERNDT FOR JOSEPH J. LEVIN; NHTSA

TO: General Engines Co. Inc.

TITLE: FMVSR INTERPRETATION

TEXT: This responds to your January 13, 1978, letter asking whether prior to September of 1976, the National Highway Traffic Safety Administration (NHTSA) required the GAWR determination to be based upon an "unrestricted" speed of 60 miles per hour.

The NHTSA requires that a vehicle's GAWR be based upon an unqualified speed of 60 miles per hour. This GAWR computation is then inserted on a vehicle's certification plate by the manufacturer to inform users of the safe GAWR. However, it is permissible to then list at the bottom of a certification plate different GAWR's based upon reduced speeds. If you intended one of your vehicles to operate under a reduced speed with a higher GAWR, you should have marked the correct GAWR on the certification label computed at 60 miles per hour and listed the higher GAWR's for the reduced speeds at the bottom of the plate.

The 1976 amendment to which you refer, Standard No. 120, continues to require the same approach to GAWR as has been the agency's practice for many years. The only difference incorporated by the 1976 amendment is that those vehicles that are unable to attain speeds of 50 miles per hour in 2 miles need not base their GAWR determination on the 60 mile per hour figure. These vehicles may compute their GAWR's at a reduced speed. Nonetheless, they are still permitted to list at the bottom of the certification plate higher GAWR's for further reduced speeds.

SINCERELY,

JANUARY 13, 1977

Joseph Levine U.S. Department of Transportation NHSTA

Reference: NMV-22 GSh CIR 1711-1

Dear Mr. Levine:

Our company has been charged by NHSTA (Office of Standards Enforcement) of building trailers during the period 1972 to September 1976 "which had tires with weight ratings less than the GAWR." This statement is true if the GAWR is calculated at the unqualified speed of 60 M.P.H. Our GAWR's were based on reduced speeds, which to the best of our knowledge was permissible at that time.

We request a legal interpretation of the following:

During the period of 1972 to August 1976 was there a specific requirement in FMVSS 49 CFR Part 567 or 571 which stated that semi-trailers were required to use an unqualified speed rating of 60 M.P.H. to determine GAWR?

To the best of our knowledge the "unrestricted" or "unqualified" speed rating requirement for GAWR certification became a requirement in September of 1976, under 571.120.

Your early attention to this question would be appreciated. We have discussed this problem with Mr. Shifflet, Mr. Buckley, and Mr. Ness.

F. W. Flowers, Jr. Vice-President