Heavy-duty Trailers.

Heavy-duty Trailers. Each manufacturer of heavy-duty trailers as specified in 49 CFR 523.10, except trailers constructed in accordance with 49 CFR 571.7(f), shall comply with the fuel consumption standards in paragraph (e)(1) of this section expressed in gallons per 1000 ton-miles. Each vehicle must be manufactured to comply for its full useful life. There are no Phase 1 standards for trailers. Different levels of stringency apply for box vans depending on features that may affect aerodynamic performance. Standards apply to the trailer vehicle families within each of the trailer regulatory subcategories in accordance with 535.4 and 40 CFR 1037.230 and based upon the applicable modeling and testing specified in 535.6.
(1) Fuel consumption standards for Box-Vans. Box van trailer families manufactured in model year 2021 and later must comply with the fuel consumption standards of this section. For model years 2018 through 2020, box van trailer manufacturers have the option to voluntarily comply with the fuel consumption standards of this section. Different levels of stringency apply for box vans depending on features that may affect aerodynamic performance. A manufacturer may optionally meet less stringent standards for different trailer types, which are characterized as follows:
(i) For trailers 35 feet or longer, a manufacturer may designate as “non-aero box vans” those box vans that have a rear lift gate or rear hinged ramp, and at least one of the following side features: Side lift gate, side-mounted pull-out platform, steps for side-door access, a drop-deck design, or belly boxes that occupy at least half the length of both sides of the trailer between the centerline of the landing gear and the leading edge of the front wheels. For trailers less than 35 feet long, manufacturers may designate as “non-aero box vans” any refrigerated box vans with at least one of the side features identified for longer trailers.
(ii) A manufacturer may designate as “partial-aero box vans” those box vans that have at least one of the side features identified in paragraph (a)(1)(i) of this section. Long box vans may also qualify as partial-aero box vans if they have a rear lift gate or rear hinged ramp. Note that this paragraph (e)(1)(ii) does not apply for box vans designated as “non-aero box vans” under paragraph (e)(1)(i) of this section.
(iii) “Full-aero box vans” are box vans that are not designated as non-aero box vans or partial-aero box vans under this paragraph (e)(1).
(iv) Fuel consumption standards apply for full-aero box vans as specified in the following table:
(1) Fuel consumption standards for Box-Vans. Box van trailer families manufactured in model year 2021 and later must comply with the fuel consumption standards of this section. For model years 2018 through 2020, box van trailer manufacturers have the option to voluntarily comply with the fuel consumption standards of this section. Different levels of stringency apply for box vans depending on features that may affect aerodynamic performance. A manufacturer may optionally meet less stringent standards for different trailer types, which are characterized as follows:
(i) For trailers 35 feet or longer, a manufacturer may designate as “non-aero box vans” those box vans that have a rear lift gate or rear hinged ramp, and at least one of the following side features: Side lift gate, side-mounted pull-out platform, steps for side-door access, a drop-deck design, or belly boxes that occupy at least half the length of both sides of the trailer between the centerline of the landing gear and the leading edge of the front wheels. For trailers less than 35 feet long, manufacturers may designate as “non-aero box vans” any refrigerated box vans with at least one of the side features identified for longer trailers.
(ii) A manufacturer may designate as “partial-aero box vans” those box vans that have at least one of the side features identified in paragraph (a)(1)(i) of this section. Long box vans may also qualify as partial-aero box vans if they have a rear lift gate or rear hinged ramp. Note that this paragraph (e)(1)(ii) does not apply for box vans designated as “non-aero box vans” under paragraph (e)(1)(i) of this section.
(iii) “Full-aero box vans” are box vans that are not designated as non-aero box vans or partial-aero box vans under this paragraph (e)(1).
(iv) Fuel consumption standards apply for full-aero box vans as specified in the following table:

Source

49 CFR § 535.5


Scoping language

None
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