Interpretation ID: aiam2123
Realco Services
Inc.
175 West Jackson Blvd.
Chicago
IL 60604;
Dear Mr. Davies: This responds to Realco Services' October 10, 1975, question whethe the replacement of the four rails in the sides of a monocoque-type van would qualify as a vehicle assembly operation subject to certification to new vehicle standards, including Standard No. 121, *Air Brake Systems*.; The answer to your question is no. The position of the NHTSA wit regard to the use of used trailer components that was discussed in the Stainless Tank and Equipment interpretation letter applies only to situations in which a new trailer body is installed on used running gear. These limitations do not apply where most of the used body (along with used running gear) is retained, as where one or more rails are replaced in the sides of a used monocoque van.; Sincerely, Frank A. Berndt, Acting Chief Counsel