In recent years, run-flat tires have become increasingly common as standard equipment in new vehicles. In theory, they provide the security of letting you limp to a safe place, even with no pressure in the tires, for a short distance.
But how would you feel if you bought a new car that didn't have run-flat tires—and it didn't have much more than a can of fix-a-flat instead?
According to Edmunds, just over the past five years, the use of run-flat tires has increased 50 percent, while they're standard on about 7.2 percent of new vehicles.
Meanwhile, last month about 13 percent of the more than a million vehicles sold in the U.S. didn't come with a spare as standard equipment, according to the LA Times.
Yes, what we're hinting at is true: Some automakers have opted to skip the spare entirely. And yes, they can get away with it. Spare tires aren't considered an essential safety feature by the federal government.
That's what Consumer Reports experienced with a long-term 2011 Hyundai Elantra test car last month. And no the goopy filler didn't work (who does have luck with the stuff, anyway?) and they did have to call roadside assistance.
The Elantra, 2011 Chevrolet Cruze and Malibu, and 2012 Buick Regal GS are among the latest models to forgo a spare. Omitting the spare entirely cuts weight, saves money. In the Cruze, dropping it in favor of a tire-inflation kit saves about 26 pounds, and Hyundai told the LA Times that the omission in the Elantra saves about $22 per vehicle.
And with wheels getting progressively larger in recent years, the costs and packaging issues in supplying a spare have been compounded.
compact spare tire, in 2011 Nissan 370Z TouringEnlarge Photo
Very few normal passenger cars come with full-size spares anymore, while more than 51 percent of vehicles come with 'donut'-style temporary spares—like the one to the left, in our current 2011 Nissan 370Z Touring test vehicle (and note Nissan's tight packaging of the Bose amp within the spare).
As we've outlined in the past, run-flat tires aren't always a great solution anyway; they still tend to be slightly harsher for road noise and are sometimes much more expensive to replace.
With modern tires, argue automakers, flats are less likely to occur, and more motorists have roadside assistance and flatbed services.
At least for the first few years. And then you're on your own—with a can of fix-a-flat.