It's probably the battle that will do most to determine the carbon emission from new U.S. vehicles over the next decade.

Automakers want to modify, delay, or extend the current corporate average fuel economy standards for 2022 through 2025 vehicles; regulators don't.

The mid-July release of the EPA's Technical Assessment Report opened a 60-day window for the public at large to comment on whether those standards should change.

DON'T MISS: Automaker lobbyist group predicts doom, gloom over CAFE

A large lobbying group led by the Alliance of Automobile Manufacturers had requested that the time period of comments be extended past its scheduled end date of September 16.

The group, numbering 16 organizations altogether, represented most automakers now building vehicles in the U.S. and other industry organizations. It did not include electric-car maker Tesla Motors.

On Monday, the answer came back. As The Detroit News notes, it was simple: No.

2015 Ford F-150 2WD Reg Cab 122.5

2015 Ford F-150 2WD Reg Cab 122.5

That response suggests to some that the regulators are inclined to leave the standards in place—as a few insiders had predicted as long as 18 months ago.

“It’s clear the government understands the fuel-efficiency challenge automakers will face because of shifting consumer preference toward trucks and SUVs," said Karl Brauer, a senior analyst for Kelley Blue Book.

ALSO SEE: Battle over CAFE standards begins now: will they change for 2022-2025?

But, he said, "it’s also clear the government doesn’t care," because carmakers have been able to comply with the standards for 2012 through 2017 vehicles.

They've done, Brauer said, "an excellent job keeping up with the rising CAFE standards thus far. So good, in fact, that the EPA isn’t going to cut them any slack on the rising standards going forward."

Gas pump

Gas pump

The three regulatory agencies that jointly issued the original CAFE standards are the U.S. Environmental Protection Agency, the National Highway Traffic Safety Administration, and the powerful California Air Resources Board.

Under the present rules, vehicle manufacturers face fines of $5.50 for each 0.1-miles-per-gallon their entire sales volume misses the required fuel-economy level for any given model year, multiplied by the total number of vehicles within that number that doesn't meet the required standard for its class.

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Regardless of what happens to those standards, at least a few economists and business groups have suggested the standards will have to be relaxed in the ending years anyway to protect the U.S. industry—whose profits rely disproportionately on trucks, SUVs, and crossover utility vehicles.

Numerous environmental, climate-change, and public-interest groups have come out strongly in favor of maintaining the existing CAFE standards, which apply to cars sold in model years 2012 through 2025.


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