Interpretation ID: nht80-2.13

DATE: 04/22/80

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: Kenworth Truck Co.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your telephone conversation with Mr. Schwartz of my office in which you asked whether net brake horsepower must be decipherable from the engine type encoded in the vehicle identification number (VIN) of heavy trucks.

The precise net brake horsepower of heavy trucks (or any other vehicle class or type) need not be encoded. This was the point which the agency was making in its March 22, 1979 (44 FR 17489) statement that:

(While) net brake horsepower is among the characteristics to be considered in establishing an engine type, there is no requirement that it be encoded in the engine type code. In some instances, such as with heavy truck engines, encodement would not be practicable.

However, except as provided below, the range of net brake horsepower must be encoded to differentiate engine types as required by section 4.5.2 of Federal Motor Vehicle Safety Standard 115. To define the acceptable range of net brake horsepower for a single engine type, the agency made a clarifying amendment to that section (February 25, 1980; 45 FR 12257). Footnote 1 to Table I provides that otherwise identical engines having net brake horsepower ratings that vary up to plus or minus 10 percent, may be treated as being of the same engine type.

The exception to the requirement to encode the range of net brake horsepower involves manufacturers which intend to utilize more than 33 engine types whose horsepower ranges fall outside of the plus or minus 10 percent parameters. These manufacturers will be unable to encode their current or anticipated engine types utilizing only a single VIN position since there are 33 separate characters authorized to be used for each VIN position. Consequently, they need not encode net brake horsepower in any way. The agency did not intend that more than one VIN position be used to encode net brake horsepower. Using more than one position would be impracticable at this time given the amount of information that needs to be encoded in the VIN.

Please contact Mr. Schwartz should have any further questions concerning this subject.