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Interpretation ID: nht79-4.33

DATE: 06/26/79

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Viking Truck Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of June 6, 1979, asking whether a rear lamp configuration that you describe would meet the location requirements of Federal Motor Vehicle Safety Standard No. 108.

Viking Truck would like to use a lighting module containing turn signal lamps, stop lamps, tail lamps, and back-up lamps mounted on its "Bridgemaster" extendable axle. This "axle" has the appearance of a small trailer and in either extended or unextended position covers about half of the rear of the concrete mixer truck to which it is attached. You stated that Viking has had problems connected with vibration and damageability when the lamps are placed on the tag axle fender, and that remounting them on the extendable axle would alleviate these problems.

Table II of Standard No. 108 requires that stop lamps, turn signal lamps, and tail lamps be mounted "as far apart as practicable." Because the National Traffic and Motor Vehicle Safety Act establishes a manufacturer self-certification scheme, the agency has traditionally deferred to a manufacturer's determination of what, in any given instance, is "practicable" except in such instances as appear to the agency to be a clear abuse of discretion. In our opinion, Viking has a reasonable basis for a determination that the location it wishes to use is practicable. In the absence of any investigation of the matter by NHTSA, or questioning of your practice, Viking's certification of compliance attached to the vehicle should ensure that the truck cannot be refused registration in any State simply because of the lighting configuration. This means, in our opinion and to answer your second question, Viking need not acquire State approval of the configuration before offering the truck for sale.

I hope this answers your questions.

SINCERELY,

VIKING TRUCK CORPORATION

June 6, 1979

Chief Council National Highway Traffic Safety Administration Room 5219, DOT Headquarters

Gentlemen:

Enclosed you will find four photographs of a concrete mixer mounted with our "Bridgemaster" extendable axle. Two of these pictures show the axle fully extended. The other two show the axle completely retracted.

Please notice the location of the light module we have put into place. This lighting module, produced by Betts Safety Lamp, is a completely enclosed, waterproof, heavy duty lighting system. In the module are the left and right turn lights, brake lights and tail lights. The back up light and electrical junction block is also included in the module. The combination brake, turn, and tail lights are 18 1/4" from center to center. Also, please notice the rear clearance lamps on the fender of the rear driving axle.

We have had numerous problems with the lights when they are placed on the tag axle fenders. They receive a lot of vibration and have a tendency to get backed into. We believe mounting the lights in the location shown in the photographs would alleviate many of our rear lighting problems.

Would the brake, turn, and tail lights, as placed in the photographs, meet the requirements of being "as far apart as practicable" (Part 571; S108-11)? If you find these lights in accordance with the regulations, do we have to acquire approval from the individual states, particularly California?

Please contact me if you need any further information. Thank you.

Michael W. Brooks

(Graphics omitted)