Night falls on automobile nation. (Nikki Kahn / Washington Post)

Ford last month sent letters to 14,000 of its American drivers with an unusual suggestion: For extra cash, they could rent their cars to fellow urbanites wanting a cheap ride.

America's second-biggest auto giant wouldn't directly sell any additional cars or trucks off the arrangement; it wouldn't even take a cut. But it would put Ford closer to the front of a movement in which cars are shared, ignored or Uber-ed — not bought.

The "peer-to-peer" rental experiment is only the latest weird move for America's auto powerhouse, maker of the F-150 and Model T. Last month, Ford launched a pay-as-you-go network of shareable, on-demand cars in London, called GoDrive.

And on Tuesday, the car giant introduced a new foldable, battery-powered "e-bike," the MoDe:Flex, with companion smartphone and Android smartwatch apps that alert cyclists to weather, directions and even upcoming potholes.

Ford focuses on transportation beyond vehicles in urban environments in video released as the company introduces its new "e-bike." (Ford)

Call it a late-life identity crisis. Ford and other carmakers, the chief benefactors of America's auto addiction, are suddenly facing a future in which car buying is a thing of the past. That future, of course, could still be far off: U.S. auto sales are running at a rate that could hit 17 million new cars this year, a 14-year high.

But in the meantime, car-sharing and taxi services like Lyft, Uber and Zipcar have exploded in cities where traffic and parking prices have soared; even kids are hailing a ride. And autonomous-car boosters promise a future where one self-driving sedan can shepherd a big crew of passengers between work, home and everywhere else, without even needing to park.

Instead of depending on the business model that's kept them going all these years, rolling new cars and trucks off the lot, Ford is trying desperately to, in the words of chief executive Mark Fields, "challenge custom and question tradition" even if that tradition helped them survive.

"We've been watching how mobility has changed in recent months and are very interested in learning how this would appeal," said David McClelland, a vice president of marketing at Ford Motor Credit, the automaker's lending arm. "It's really important for us to learn what our customers do, what they rent out and, as a result, what our next steps will be."

[The many reasons millennials are shunning cars]

The car-sharing program, running now through November, will cover cars, trucks and SUVs in six of America's younger cities: Berkeley, Oakland, San Francisco, Portland, Chicago and Washington. The Ford-financed vehicles are rented to pre-screened drivers through Getaround, an Airbnb for cars, for anywhere between $5 and $9 an hour.

Getaround takes a 40 percent cut, but Ford gets a few perks, too: The car owners get more money to pay off loans, and the renters take a test drive that could persuade them to buy a Ford, if they ever buy a car at all.

But Ford isn't just betting all on car-rentals or smart bikes. On Tuesday, Ford announced its team in Palo Alto focused on self-driving vehicles was moving from research to "advanced engineering." The carmaker also said it would install new driver-assist technologies (sometimes called "semi-driverless" upgrades, like highway auto-pilot and automatic brakes) across its fleet within the next five years.

For another experimental program, the automaker has designed a "dynamic social shuttle" built around an Uber-like app that could pick up and drop off up to 15 riders in a Ford "premium mini-bus." The program is being tested in London this year.

[Ford is experimenting with its own Uber-like app — and a vehicle to go with it]

Considering the last few years of surging car sales, it would be far easier for the auto world to rest on its laurels. But a recent Global Automotive Outlook report by consulting firm AlixPartners predicted auto sales would peak next year amid rapid industry change. Car-sharing services worldwide now count about 5 million members, the report said, and will grow to 26 million members within five years.

Studies show millennials, the biggest generation in U.S. history, drive far less than their older (wiser) neighbors. And Ford executives cited a poll by researcher Penn Schoen Berland that found one-third of American millennials were interested in renting out their stuff in order to boost their income, with most ranking "rides in a car" as the second-best rentable (behind books).

Public-policy experts say borrowing, renting and sharing cars makes a lot more sense, anyway. Our vehicles spend far more of their lives baking in a parking lot than on the road: One U.K. study suggests the typical passenger vehicle is parked 96 percent of the time.

It's not exactly the kind of sentiment you can imagine Henry Ford agreeing with. But considering what Ford calls the "different futures in mobility,” it may be the only way the company stays alive.

Services like Uber and Zipcar, Ford executive chairman Bill Ford told Bloomberg last month, are "changing the way we use our vehicles. And it’s happening really fast. ... There’s no question our business model will look very different in the future than it does today."

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