Forgot the car keys? You may not need them anymore
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Officially, it isn't a recall, just a technical service bulletin.

Whatever General Motors (GM) is calling the announcement, dealers have been advised to replace the keys on 2014 and 2015 Chevrolet Silverado and GMC Sierra models, as well as several other large vehicles. That development may herald a wider shift in the auto industry to cars that no longer rely on keys.

Some owners have complained that when they shift gears, they can knock the key out of position-bringing to mind this year's recall of GM vehicles with defective ignition switches.

That recall, as well as several others in the auto industry in recent years, is adding momentum to a broad industry shift away from conventional ignition switches.

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"Eventually, the key will go away," said Dave Sullivan, manager of product analysis at AutoPacific. Sullivan said he expects only a handful of models-mostly base-level trucks-will continue to use conventional ignition systems.

That view has been echoed by automotive firm Edmunds.com. Its research found that some form of push-button switch was available-either as a standard feature or an option-on 72 percent of the cars and trucks sold in the U.S. during the 2014 model year.

There are a variety of different types of keyless ignitions. Some simply eliminate the key but still require a driver to turn a knob on the side of the steering column. Most others have use push-button starters.

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Virtually every Nissan (Tokyo Stock Exchange: 7201.T-JP) model now uses a version of the Japanese maker's Intelligent Key system, from the entry-level Versa up to the top-line Infiniti QX80 SUV. Ford (NYSE:F) has abandoned keys on all but its two new van models, the full-size Transit and midsize Transit Connect.

Meanwhile, General Motors CEO Mary Barra told members of the House Energy & Commerce Committee during a hearing on its ignition switch recall that "the push-button start is something we're evaluating putting across the portfolio."

As the various GM recalls have underscored, keyed ignition systems can inadvertently be jostled out of position. When that happens, a vehicle can shut off, causing the driver to lose control. But safety is just one reason why manufactures are looking for alternatives.

"Real estate is at a premium," Sullivan said, noting that automotive designers and engineers are trying to clear space to squeeze in more technologies.