Interpretation ID: aiam2521
Vice President - Engineering
5990 N. Washington Street
Denver
CO 80216;
Dear Mr. Gromer: This responds to Timpte's January 11, 1977, question whether NHTS regulations prohibit sale and delivery of a trailer to the first purchaser equipped with two used tires in place of the eight tires that are specified for the vehicle and which would form the basis of certification under Part 567, *Certification* and the basis of compliance with Standard No. 120, *Tire Selection and Rims for Vehicles Other Than Passenger Cars*.; As you are aware, Part 567 of our regulations requires a statement b the vehicle manufacturer of the gross axle weight rating (GAWR) for each axle on any motor vehicle it manufactures (S 567.4(g)(4)). The term 'GAWR' is defined in S 571.3 of our regulations as the value specified by the manufacturer as the load-carrying capacity of the axle system, measured at the tire- ground interfaces. This clearly means that the tires and wheels on an axle must be taken into account in assigning a GAWR value for certification purposes.; Standard No. 120 specifies that 'each vehicle . . . shall be equippe with tires that meet specified requirements ' (S5.1.1) but makes provision for the installation of used tires owned by the purchaser if the maximum load ratings of the tires on an axle system are at least equal to the GAWR assigned to the axle system by the vehicle manufacturer (S5.1.3). Section S5.1.3 reflects the agency's view that existing commercial practices for the delivery of vehicles with safe used tires has not created a significant safety problem to date.; In recognition of varying commercial practices for the delivery o vehicles, the agency has interpreted S5.1.1 of Standard No. 120 to prohibit the installation of tires that do not meet certain performance requirements, but not as a requirement that tires be fitted to every axle of a vehicle prior to certification and sale. A copy of this interpretation is enclosed for your information. The interpretation makes clear that, while the agency interprets Standard No. 120 (and by implication Part 567) to permit the assignment of a GAWR on the basis of tires listed on the certification plate, the assignment of an arbitrarily high (or low) GAWR for purposes such as avoiding a Federal motor vehicle safety standard could constitute a violation of law.; With regard to the practice you describe of delivering an empty ne trailer to the purchaser on fewer tires that (sic) necessary to conform to the GAWR listed on the certification plate and the minimum requirements of S5.1.1 and S5.1.2 of Standard No. 120, the agency interprets its motor vehicle safety standard and S 567.4(g)(4) to permit such a good faith delivery practice. In the event any pattern of avoidance of Federal requirements becomes apparent, however, the agency would reconsider this interpretation.; Sincerely, Frank Berndt, Acting Chief Counsel