Vans are the most tightly regulated type of trailer under the proposed rulemaking developed by the EPA and NHTSA. The joint proposal was officially published July 13.

Mandating fuel efficient trailers

Aug. 6, 2015
NHTSA, EPA publish proposal to regulate trailer emissions, fuel economy

FOR the first time, the federal government will regulate the fuel efficiency and greenhouse gas emissions of vehicles that do not contain engines.

NHTSA and EPA officials made their plans official with a notice of proposed rulemaking July 13, formalizing their plan to include truck trailers in the latest round of fuel economy and greenhouse gas regulations for commercial vehicles.

Trailer aerodynamics, rolling resistance, and tare weight all impact fuel consumption of the tractors that pull them. That’s why regulators chose to include trailers in Phase 2 of regulations aimed at medium and heavy duty commercial trucks.

The EPA/NHTSA proposal is scheduled to become increasingly stringent until fully implemented in 2027. The phase-in is intended to allow time for new technologies and products to be introduced.

The proposed rule will set CO2 emission and fuel consumption standards for manufacturers of new trailers. The proposed rule is scheduled to take effect with the 2018 model year and would be voluntary for trailer manufacturers until the 2021 model year.

Once the rule kicks in, the requirements will become increasingly stringent until the full impact of the regulation takes effect with the 2027 model year. At full strength, the rule is expected to improve fuel economy between 3% and 8% with a corresponding reduction in greenhouse gas emissions.

The proposal will impact the vast majority of highway trailers. Vans will be the primary target in part because every conventional means of reducing fuel consumption—aerodynamic devices, low rolling resistance tires, automatic tire inflation systems—can be applied to them. In fact, the proposal creates nine different categories of vans and puts everything else in one big bucket—“Non-box trailers.”

Here is how the rule will categorize the affected trailers:

•  Long box trailers (dry-freight vans) longer than 50 feet.

•  Long box refrigerated trailers (longer than 50 feet).

•  Short box (50 feet or less) dry-freight vans.

•  Short box (50 feet or less) refrigerated vans.

•  Partial-aero long box dry vans.

•  Partial-aero long box refrigerated vans.

•  Partial-aero short box dry vans.

•  Partial-aero short box refrigerated vans.

•  Non-aero box vans (all lengths of dry and refrigerated vans).

•  Non-box trailers (tanker, platform, container chassis, and all other types of highway trailers that are not box trailers).

Potential for fuel savings varies by trailer design and operation. Recognizing this, NHTSA and EPA performance levels will vary by trailer type. For example: Partial aero trailers—those trailers that have liftgates or other equipment that limit the ability to install full aerodynamic devices—will not be able to manage aerodynamic drag as effectively. The same is true for shorter trailers. Because shorter trailers tend to be used in local delivery operations where speeds are lower, the potential for reducing aerodynamic drag in shorter trailers may be less.

The proposed rule completely excludes several types of trailers, including certain logging and mining trailers, heavy-haul trailers, and trailers such as fracking trailers where the primary function of the trailer is performed while stationary.

Maintenance requirements

In general, EPA requires that vehicle manufacturers specify maintenance schedules to keep their product in compliance with emission standards throughout the useful life of the vehicle. The proposal considers the useful life of a trailer to be 10 years.

For trailers, such maintenance could include fairing adjustments and servicing automatic tire inflation systems. EPA believes that fleets, rather than the trailer manufacturer, will probably perform the maintenance in order to maintain the fuel savings the components are expected to provide. The agency is not requiring trailer manufacturers to submit a maintenance schedule for these components as part of its application for certification.

Neither is the agency proposing to hold trailer manufacturers responsible for the actions of operators. For example, EPA believes trailer operators will replace the low rolling resistance tires with similar tires because of the reduced operating costs that they are expected to provide.

However, the proposal does require trailer manufacturers to put information in the owner’s manual that helps them buy tires that meet or exceed the rolling resistance performance of the original equipment tires.

Trailer OEM certification

Under the proposed structure, trailer manufacturers would have to obtain a certificate of conformity from EPA before bringing new trailers to market.

The certification process the agencies are proposing for trailer manufacturers is similar to the process for the tractor program. This structure involves pre-certification activities, the certification application and its approval, and end-of-year reporting.

Trailer manufacturers have several options to test for compliance, including:

•  A customized vehicle simulation model (GEM) that EPA developed for the Phase 1 program. The agency has developed an equation based on GEM that calculates CO2 and fuel consumption from performance inputs, but without running the model.

For the proposed trailer program, the trailer characteristics that a manufacturer would supply to the equation include aerodynamic improvements such as change in the aerodynamic drag area, tire rolling resistance, the presence of an automatic tire inflation system, and the use of light-weight components from a pre-determined list. The use of the equation would quantify the overall performance of the trailer in terms of CO2 emissions and fuel consumption on a per ton-mile basis.

•  A general certification process. Under the proposed process for certification, trailer manufacturers would be required to apply to EPA for certification and would provide performance test data. Trailer manufacturers would submit their applications through the EPA VERIFY electronic database, and EPA would issue certificates based on the information provided.

At the end of the model year, trailer manufacturers would submit an end-of-year report to the agencies to complete their annual obligations.

Comments requested

The public has until September 11 to comment on the proposal. EPA and NHTSA specifically asked for comments on a range of trailer-related topics. Among them:

•  Credit and banking. Should the program allow credit and deficit banking and credit trading? Comments supporting averaging, banking, or trading should explain how these provisions would be valuable for trailer manufacturers across the industry, including how the provisions would maintain a ``level playing field.'' The agencies are proposing not to include banking and trading provisions in any part of the program, and are limiting the option to average to manufacturers of dry-freight and refrigerated trailers.

•  Underride guard conflicts. What is the relationship between underride guards and the possible installation of rear aerodynamic fairings?

•  No aerodynamic requirements. The agencies are not proposing CO2 or fuel consumption standards predicated on aerodynamic improvements for non-box trailers or non-aero box vans at any stage of this proposed program. Manufacturers of these trailers would only be required to adopt specific tire technologies. Good idea or not?

•  Right length? The proposal distinguishes between long and short trailers, with 50-foot lengths the line of demarcation. Is this appropriate?

•  Cost/benefit analysis. Is the stringency of the standards in relation to their cost, CO2 and fuel consumption reductions appropriate?

•  Unfolding. Boat trails be used at the rear of trailers if they do not deploy automatically?

•  Weight reduction. The agencies are proposing compliance provisions that would limit the weight-reduction options to the substitution of specified components that can be clearly isolated from the trailer as a whole. The agencies have identified 11 common trailer components that have lighter weight options available, such as substituting conventional dual tires mounted on steel wheels with wide-based single tires mounted on aluminum wheels. The agencies recognize that when weight reduction is applied to a trailer, some operators will replace that saved weight with additional payload. The agencies are proposing standards that could be met without reducing weight. Is this appropriate?

These and many other comment requests can be found in the Federal Register proposal. Comments can be made online at and emailed to [email protected]

From August 5 – September 6, 2015, Trailer/Body Builders will run a weekly poll on several of the above questions. Participate in the weekly poll found on our home page.

 These polls will be simple 'yes' or 'no' questions. If you have more to say or to add to the discussion, we encourage you to use the Comment feature at the end of this article to get the conversation started!

About the Author

Bruce Sauer | Editor

Bruce Sauer has been writing about the truck trailer, truck body and truck equipment industries since joining Trailer/Body Builders as an associate editor in 1974. During his career at Trailer/Body Builders, he has served as the magazine's managing editor and executive editor before being named editor of the magazine in 1999. He holds a Bachelor of Journalism degree from the University of Texas at Austin.