49 C.F.R. § 537.4
Definitions.
Cite as 49 C.F.R. § 537.4 (2026)
(a)
Statutory terms.
(1) The terms
average fuel economy standard, fuel, manufacture,
and
model year
are used as defined in 49 U.S.C. 32901.
(2) The term
manufacturer
is used as defined in 49 U.S.C. 32901 and in accordance with part 529 of this chapter.
(3) The terms
average fuel economy, fuel economy,
and
model type
are used as defined in subpart A of 40 CFR part 600.
(4) The terms
automobile, automobile capable of off-highway operation,
and
passenger automobile
are used as defined in 49 U.S.C. 32901 and in accordance with the determinations in part 523 of this chapter.
(b)
Other terms.
(1) The term
loaded vehicle weight
is used as defined in subpart A of 40 CFR part 86.
(2) The terms
axle ratio, base level, body style, car line, combined fuel economy, engine code, equivalent test weight, gross vehicle weight, inertia weight, transmission class,
and
vehicle configuration
are used as defined in subpart A of 40 CFR part 600.
(3) The term
light truck
is used as defined in part 523 of this chapter and in accordance with determinations in that part.
(4) The terms
approach angle, axle clearance, brakeover angle, cargo carrying volume, departure angle, passenger carrying volume, running clearance,
and
temporary living quarters
are used as defined in part 523 of this chapter.
(5) The term
incomplete automobile manufacturer
is used as defined in part 529 of this chapter.
(6) As used in this part, unless otherwise required by the context:
(i)
Administrator
means the Administrator of the National Highway Traffic Safety Administration or the Administrator's delegate.
(ii)
Current model year
means:
(A) In the case of a pre-model year report, the full model year immediately following the period during which that report is required by § 537.5(b) to be submitted.
(B) In the case of a mid-model year report, the model year during which that report is required by § 537.5(b) to be submitted.
(iii)
Average
means a production-weighted harmonic average.
(iv)
Total drive ratio
means the ratio of an automobile's engine rotational speed (in revolutions per minute) to the automobile's forward speed (in miles per hour).
[89 FR 52953, June 24, 2024]
- Cross-references to the US Code
- 49:3290149:32901.
- Cross-references to the CFR
- 537.5