2017 Ford Fusion - Image: FordAcross the U.S. auto industry, there are a number of auto brands that are actually selling more passenger cars in 2017 than in 2016: Jaguar, Lincoln, Infiniti, Subaru, Volkswagen.

Some specific models, many with all-wheel-drive availability like the Audi A5, Subaru Impreza, and Volkswagen Golf, are enjoying far greater sales success this year than last.

But you know the story. Generally speaking, Americans are buying far fewer cars now than they used to. From more than 50 percent just five years ago, passenger car market share is down to 37 percent. Nowhere is this more obvious than at traditional domestic manufacturers, the Detroit Three.

While the U.S. auto industry has reported a drop of 3 percent compared with 2016’s record sales pace, passenger car sales have fallen four times faster than that. But the domestic drop is far more severe than the decline faced by import marques.

Buick, Cadillac, Chevrolet, Chrysler, Dodge, Ford, and Lincoln combined to lose 19 percent of their car sales volume so far this year. All other brands were down “just” 9 percent. As a result, these traditional Detroit brands saw their share of the U.S. passenger car market fall from 36 percent in 2016’s first eight months to 25 percent in the first eight months of 2017, a massive decline over the span of just one year.2018 Cadillac CTS - Image: CadillacAfter discovering that foreign automakers will likely build more vehicles than the Detroit Three in America this year, we wanted to take a look at the root cause of the downturn at General Motors, Ford Motor Company, and Fiat Chrysler Automobiles.

It’s certainly not pickup trucks.

It’s cars.

GM, Ford, and FCA are ending shifts at car plants, laying off workers, and discontinuing models all because America’s consumers are turning away from Detroit-branded cars far faster than they’re turning away from cars in general. The brands are attempting to gradually wean themselves off fleet-reliance, as well.

There are a handful of notable exceptions to the general theme of decline, but in many of those cases, there’s a simple explanation. Chevrolet Cruze sales, for instance, are up 9 percent this year. But that’s only after an awful 2016 — compared with 2015, Cruze volume is down 18 percent this year. The Cadillac CT6’s 77-percent jump is simply a quirk of a 2016 calendar that didn’t provide any meaningful CT6 totals until May. Over the last four months, CT6 sales are up 1 percent. Big increases from the Chevrolet SS and Dodge Viper come as dealers clear out remaining models.

For the most part, Detroit’s cars are fading. And fast.

[Images: Ford, General Motors]

Timothy Cain is a contributing analyst at The Truth About Cars and Autofocus.ca and the founder and former editor of GoodCarBadCar.net. Follow on Twitter @timcaincars and Instagram.