Interpretation ID: aiam1930
President
Toledo Clutch & Brake Service
Inc.
2112-24 Monroe Street
Toledo
OH 43624;
Dear Mr. Schlichting: This responds to your April 21, 1975, questions whether a 121-equippe chassis must be certified to Standard No. 121, *Air brake systems*, after installation of a tractor conversion kit, whether an antilock wiring harness may be spliced for purposes of frame extension, whether additional weight (such as a body) or an axle may be added to a vehicle after it is sold and put into use, and whether the standard regulates the replacement of worn brake components. You state that it should be assumed that the vehicle has been delivered to the first user.; The National Traffic and Motor Vehicle Safety Act prohibits th manufacture for sale, sale, offer for sale, introduction into interstate commerce, or importation of a vehicle which does not comply with all applicable standards in effect on the date of manufacture. (15 U.S.C. 1397(a)(1)(A)). However, the Act also provides that this prohibition no longer applies to a vehicle (except in the case of importation) after the first purchase of it in good faith for purposes other than resale. (15 U.S.C. 1397(b)(1)). The Act also prohibits any manufacturer, distributor, dealer, or motor vehicle repair business from knowingly rendering inoperative a safety device or design (15 U.S.C. 1397(a)(2)(A)).; These provisions mean that the manufacturer of the vehicle must assum responsibility for compliance and certification. Most trucks are built in several stages and completed by final-stage manufacturers like yourself. Cab-chassis are only incomplete vehicles which have not been certified, and therefore, whoever completes the vehicle and subsequently sells it or introduces it on the public highway must certify its compliance. In answer to your first question, it is the responsibility of the person who installs the fifth wheel, tractor protection system, etc., to certify compliance, whether or not the vehicle has been delivered to the first user. The owner himself would qualify as a final-stage manufacturer if he installed the conversion kit.; In answer to your third and fourth questions, the installation would b subject to certification unless it followed 'the first purchase of it in good faith for purposes other than resale.' 'Good faith' means that the first user could not, for example, buy a completed vehicle, drive it around the block and then install a non-conforming tag axle. Installation of a body after delivery to the first purchaser without compliance with Standard No. 121 would in most cases not appear to be good faith because the vehicle is not capable of use without the body.; It is permissible to make modifications to a vehicle that is already i service after the first purchase in good faith. A private party may make any change, but as noted above, a manufacturer, distributor, dealer, or motor vehicle repair business such as yours cannot 'knowingly render inoperative' a safety device in the process of modification. In answer to question number five, Standard No. 121 regulates the manufacture of new vehicles only and does not contain provisions which limit use of replacement parts. The only restriction in replacement would be to avoid knowingly rendering inoperative safety devices or design.; In answer to question number three, the standard establishe performance levels and does not contain any design requirements concerning the wiring harness of antilock systems. We would advise that you contact the antilock manufacturer or the vehicle manufacturer as to the wisdom of splicing antilock wiring.; For your information, I enclose a discussion of the standard whic addresses final-stage manufacture at page seven.; Yours truly, Richard B. Dyson, Assistant Chief Counsel