WASHINGTON -- Federal regulators said they may require an interim review of 2017-25 fuel-economy standards, as automakers have requested.
But the date floated for such a review has split the leading manufacturing groups.
The Alliance of Automobile Manufacturers said the Obama administration's tentative plan doesn't call for an early enough assessment.
The National Highway Traffic Safety Administration said last month that it might consider two separate procedures for setting corporate average fuel economy standards -- one for 2017-21 models, another for 2022-25 models -- because NHTSA is limited by law to setting targets for five years or less.
"We need reviews every few years," said Gloria Bergquist, a spokeswoman for the alliance, whose members include General Motors, Toyota and Ford. "Additional variables such as fuel costs, fueling infrastructure and consumer uptake of fuel-efficient technologies represent huge unknowns." The alliance wants an intermediate review in 2019, allowing time to modify the standards two years later, she said.
But the Association of Global Automakers supports the administration's tentative plan. Members include Honda, Hyundai and Nissan.
NHTSA and the EPA are working jointly to set mpg and emission standards, as they did for the 2012-16 model years. The Obama administration is consulting with automakers, California regulators and environmental groups as it prepares a September proposal for mpg and emissions standards. Final adoption of the rule is due in July 2012.
Recent talks have touched on whether there should be an interim review and, if so, when, industry officials said.
We've "received a positive reception," Bergquist said, adding: "The ability to predict costs and technology advancements becomes much more uncertain beginning in model year 2021."
With the fuel economy standards peaking at 35.5 mpg in 2016, the administration has floated preliminary targets of 47 to 62 mpg for 2025.
Automaker groups have been pursuing three goals: a single national standard, an interim review of that standard and no adoption of 62 mpg until further studies are completed.
The Union of Concerned Scientists, which favors a 62-mpg standard, criticized the alliance's position on a 2019 review.
"We don't want an incentive for manufacturers to delay the introduction of fuel-saving technology," said James Kliesch, a UCS research director. "During the first half of the next round, only modest improvements will be needed over 2016 levels."