Interpretation ID: nht89-1.88

TYPE: Interpretation-NHTSA

DATE: May 12, 1989

FROM: Donald W. Vierimaa -- Vice President-Engineering, Truck Trailer Manufacturers Association

TO: Billy Mohr -- Commander, Support Section, Motor Carrier Division, Department of State Police

TITLE: None

ATTACHMT: Attached to letter dated 6/1/94 from John Womack to Donald W. Vierimaa (VSA S103(a)), letter dated 8/9/93 from Donald W. Vierimaa to John Womack and letter dated 5/16/89 from Billy Mohr to Donald W. Vierimaa

TEXT:

Please advise us as to whether he attached sketches properly interpret the Michigan bumper, trailer "wheelbase", and side marker lamp requirements for the length of trailers shown. We would appreciate a copy of the actual regulations or law for referenc e purposes describing the bumper, lighting, and kingpin to center of tandem/single axle requirements.

Regarding the lighting requirements for trailers longer than 50 feet as described in your letter of March 27, 1989, we assume that the "two clearance lamps" described in (8)(c) of the regulations describes the "intermediate side marker lamps" regulated b y NHTSA in FMVSS 108. If indeed Michigan is requiring two additional intermediate side marker lamps to those required by FMVSS 108, then it would appear that your requirement is invalid as FMVSS 108 preempts State regulations which substantially differ. Please see excerpts from NHTSA legal interpretations on this subject in the attachment to TTMA RP No. 9, section 1.0.

Thank you in advance for further clarifying your regulations for our member trailer manufacturers.