Interpretation ID: nht71-5.5

DATE: 11/22/71

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Mr. James Eckstein

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of August 27, 1971, which was forwarded to this office October 20, 1971, by the Federal Trade Commission, regarding Government specifications for retreaded tires. You refer to problems you believe result from "out of roundness;" specifically, abnormal wear and blowouts at normal boulevard and highway speeds. You wish to determine whether this problem results from "too lenient" Government requirements, or whether "manufacturers are negligent."

Out-of-roundness can occur in a retreaded tire for numerous reasons, and its presence does not necessarily indicate negligence on the part of the manufacturer. Moreover, while an out-of-round tire may affect vehicle handling it generally does not blow out at normal boulevard or even highway speeds, as a result of the out-of-round condition. Thus, a blow out in an out-of-round tire could have resulted from other factors. Many tire dealers, in addition, have machines that can eliminate out-of-roundness by cutting off excess tread.

With reference to Federal regulations of retreaded tires, the first such regulation will become effective January 1, 1972. This regulation, Motor Vehicle Safety Standard No. 117, "Retreaded Pneumatic Tires," specifies size and performance requirements for retreaded tires for use on passenger cars. These requirements are similar to those that have been applicable to new passenger car tires since January 1, 1968. None of these requirements specifically concern "out-of-roundness." We do not have evidence that this characteristic, by itself, is a safety problem.