Under the new administration of President Donald Trump, the EPA has reopened comments on its decision to finalize emission rules for 2022 through 2025 vehicles.

Meanwhile, the NHTSA—which sets fuel-economy rules that have to correspond to EPA limits on carbon-dioxide emissions—hasn't yet issued its corporate average fuel-economy rules for that same period.

Now, a bipartisan group of senators has introduced a bill that roughly keeps current standards in places but gives makers of light trucks and utility vehicles additional credits toward meeting those rules.

DON'T MISS: Automakers say fuel-economy rules hurt buyers; Consumers Union rebuts claim

Introduced by Senators Roy Blunt [R-MO], Debbie Stabenow [D-MI], Jerry Moran [R-KS], Gary Peters [D-MI], Todd Young [R-IN], and Claire McCaskill [D-MO], the proposed legislation (S1273) would give automakers retroactive credit for improvements already made in earlier model years.

It would also allow manufacturers to transfer credits between cars and trucks,  meaning that cars that overachieve on the requirements could provide credits to offset underachieving light-duty trucks.

Such transfers weren't previously allowed under CAFE rules through the 2021 model year.

2017 Toyota RAV4

2017 Toyota RAV4

Automakers have argued that because light-duty trucks—which include the crossover utility vehicles of all sizes that have surged in popularity—now make up a far higher proportion of total sales than projected when the standards were written, the challenge of meeting those standards is greater than expected.

Light-duty trucks, of course, are generally lower in fuel efficiency than passenger cars of the same interior volume, because they are taller, higher off the ground, and usually have all-wheel drive as an option, which adds weight.

Reaction from consumer and environmental groups was swift and condemnatory.

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"The bill would allow automakers to stall implementation of fuel-saving technologies across all vehicles," said Consumers Union, "especially larger vehicles like SUVs and pick-up trucks, ultimately burdening consumers with higher fuel costs and harmful emissions."

“By using expired credits and stealing credits from cars, automakers would saddle truck owners and families with outdated gas-guzzlers instead of providing them with the modern, efficient utility vehicles they need,” said Jack Gillis of the Consumer Federation of America.

“The last thing moms or dads driving their kids to school, small business tradespeople, and large families need is to spend more money on gas.”

Old Gas Pumps

Old Gas Pumps

Environment America said that the bill, if passed, would result in approximately 350 million barrels of additional oil being burned, producing 155 million metric tons of global-warming emissions, and costing drivers an additional $34 billion in fuel.

"Make no mistake, this is yet another attempt by automakers to change the rules of the road by rolling back the consumer and climate protections Americans—and not too long ago, the auto industry—overwhelmingly support," said the Sierra Club.

Some accommodations to delay or modify the 2022-2025 CAFE rules had been expected, though it remains unclear to what degree they will be opposed by the influential California Air Resources Board.

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The bill has been referred to the Senate Committee on Commerce, Science, and Transportation.

As of this morning, the text of the bill had not yet been posted on the Congressional website.

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