exhaust-emissionsA final rule that will further entrench emissions standards and set fuel economy standards for tractor-trailers has advanced closer to publication.

The final version of the rule, officially dubbed Phase 2 of the Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Medium- and Heavy-Duty Engines and Vehicles, was sent to the White House this week for review.

The National Highway Traffic Safety Administration and the Environmental Protection Agency introduced the proposed rule last June. The standards will begin taking effect for trailers in model year 2018 and 2021 for tractors. The plan goes through 2027, when the entire vehicle ­­– engine, truck and trailer – will be required to meet the standards.

The requirements in the rule will be for truck and trailer manufacturers to meet, not buyers, but industry stakeholders during the comment period of the proposed rule said the agencies underestimated the costs that will be passed on to truck buyers.

EPA, DOT announce proposed regulations for Phase 2 of GHG, fuel efficiency standards

The proposed standards will begin in model year 2018 for trailers and 2021 for tractors and culminate in vehicle-wide — engine, truck and trailer — …

When the proposed rule was announced last year, the EPA said the standards would “significantly reduce carbon emissions and improve fuel efficiency of heavy-duty vehicles, helping to address the challenges of global climate change and energy security.”

A month later, in July, the full text of the proposed rule was released when the 629-page Notice of Proposed Rulemaking was published in the Federal Register.

The trailer standards, which will begin to be implemented first, proposed aerodynamic and tire improvements to help reduce fuel consumption of the entire tractor-trailer by 3-to-8 percent from the model year 2017 baseline.

EPA fuel economy standards: Major trucking groups, truck manufacturers question rule’s stipulations, support its goals

Some say the proposed rules are too aggressive and will be difficult to meet with the given timeline. Others say the market will drive the …

The tractor standards proposed for model year 2027 would lower carbon dioxide emissions and fuel consumption by up to 24 percent from a 2017 model Phase 1 tractor.

The agencies also proposed a 4.2 percent reduction in carbon dioxide emissions and fuel consumption from 2017 baseline engines. The engine standard requirements will begin in 2021 and become stricter in 2024 before meeting the 4.2 percent goal in 2027.

The White House Office of Management and Budget generally has 90 days to clear the rulemaking for publication in the Federal Register, barring special circumstances.