NHTSA Scraps Truck Fuel Economy Standards: What It Means

NHTSA Moves to Narrow Authority Over Standalone Truck Engine Efficiency Rules

The National Highway Traffic Safety Administration is moving to limit its authority to regulate the fuel efficiency of medium- and heavy-duty truck engines separately from the vehicles in which they are installed. The agency’s interpretive rule reverses an Obama-era policy and leaves current commercial vehicle fuel-efficiency standards in place while broader revisions are considered.

Agency Seeks to Clarify Regulatory Authority

NHTSA said it has reconsidered the scope of its authority to establish fuel economy standards for commercial medium- and heavy-duty vehicles, on-highway trucks and work trucks. Under the agency’s revised position, truck engines would not be regulated independently from the vehicles themselves.

The change would return greater responsibility to manufacturers as they determine how to meet applicable fuel-efficiency requirements. NHTSA Administrator Jonathan Morrison said the agency believes manufacturers are best positioned to develop engines and vehicles for the commercial market’s varied operating demands.

Transportation officials have also indicated that the administration is working on a broader rewrite of federal fuel economy requirements. In December, NHTSA proposed lowering fleetwide fuel economy requirements for model years 2022 through 2031. The proposal projected an industrywide average of approximately 34.5 miles per gallon for passenger cars and light trucks by model year 2031, compared with about 50.4 mpg under earlier standards.

Manufacturers Support Review

The Truck and Engine Manufacturers Association welcomed the review, saying future standards should account for real-world customer adoption of fuel-saving technologies and the operational demands of commercial fleets.

“EMA looks forward to working with NHTSA as the agency develops a final rule addressing fuel efficiency standards for medium- and heavy-duty vehicles that reflect real-world customer adoption of fuel-saving technologies, deliver meaningful operational and economic benefits to customers, and provide manufacturers the flexibility to develop engines and vehicles that meet the diverse demands of the commercial vehicle market,” the association said.

Industry Impact Remains Under Debate

EPA and NHTSA previously estimated that the broader Phase 2 greenhouse gas and fuel-efficiency program would save truck owners approximately $170 billion in fuel costs and reduce carbon dioxide emissions by roughly 1.1 billion metric tons over the lifetime of covered vehicles.

Critics of the proposed rollback have argued that weaker fuel-efficiency requirements could leave trucking companies more exposed to diesel-price volatility. Supporters of the change maintain that manufacturers need flexibility to select the technologies best suited to different vehicle applications, duty cycles and customer requirements.

The current fuel-efficiency standards for commercial trucks remain in effect. Any changes to those requirements would require additional regulatory action by NHTSA and other relevant federal agencies.