“Had I known that, I would have at least had the spare-tire kit included in negotiations,” he says.

Kronberg is not alone; many carmakers have eliminated spare tires to improve fuel economy. Some, like Kia (and Toyota, seen left), provide an inflator kit, and others have switched to run-flat tires, which can be driven for limited distances after a puncture. But run-flat tires tend to be more expensive to replace and often deliver a stiffer ride.

Because modern tires are generally reliable and flats aren’t as common as they used to be, ditching a 45-pound spare might seem like a reasonable gamble for carmakers to take to save gas. But as Kronberg points out, an inflator kit helps only if you have a small puncture in the tread. It can’t fix a tire with a sidewall puncture or more significant damage. For that, you’ll have to call a tow truck—and hope that a matching replacement tire is readily available.