The Obama administration's corporate average fuel economy standards for the 2017-25 model years are official. As expected, they will require automakers to meet the equivalent of 54.5 mpg by the 2025 model year.
Many argue that the standards are far from perfect and that the political process used to devise them was heavy-handed, with undue influence from nongovernmental organizations, rather than being a collegial, collaborative effort of industry and government as it was publicly portrayed.
But no matter. The standards are the law of the land, which means the industry needs to get on with finding ways to comply.
That may not be as easy as some outside the industry have assumed. Some engineers say they don't know how to hit 54.5 mpg in vehicles that consumers want to buy and can afford.
Last week, after the final standards were released, Chrysler CEO Sergio Marchionne said that the requirements will change the industry fundamentally, and that automakers are struggling with a number of difficult choices. He said everything is on the table, including possible elimination of popular models and powertrain combinations.
The final rules aren't much different from the those that were proposed. They still use a variety of credits to favor electrification over other clean technologies, which is the government's way of picking a winning technology rather than permitting engineers to do it. One change: The final rules do include credits for vehicles that burn compressed natural gas, which currently are only sold in small volumes by Honda.
Clean-diesel technology, favored by European automakers that have invested in it for use in other markets, is still slighted.
There are other anomalies that make it better for automakers to enlarge their vehicles to fall under a larger, more lenient, "footprint" category.
A report released Aug. 10 by the staff of U.S. Rep. Darrell Issa, R-Calif., chairman of the House Oversight Committee, said the rules discriminate in favor of the bailed-out automakers, meaning General Motors and Chrysler Group.
But after 35 years of CAFE standards that failed to distinguish between full-line American manufacturers and small-car Japanese importers, thus playing a central role in the collapse of Detroit's automakers, there are now fuel economy rules that acknowledge that pickups aren't the same as Toyota Corollas.
The new fuel economy rules have good and bad provisions. But further grousing is counterproductive, and resistance is futile. What's left is for automakers to design and build vehicles that delight customers and comply with federal regulations.