PHILADELPHIA (CBS) - Some car buyers are finding their new vehicles are not equipped with spare tires.

In an effort to meet increasingly rigid fuel economy standards, some automakers are dumping the spare tire. For example, General Motors over the last couple of years has moved toward tire inflator kits in place of heavier spares.

AAA Mid-Atlantic’s Jim Lardear says another option for manufacturers is the run-flat tire.

“It’s a pneumatic tire and it’s designed to resist getting a puncture that would deflate the tire. And it allows the vehicle to continue to be driven at a lower speed, something like 50-55 miles per hour.”

But there’s no guarantee that those options will prevent or repair a flat tire all the time. And therein lies the dilemma for motorists, says Lardear.

“AAA can come out and change a tire for you. But we’re changing it with your spare. We’re not coming out and bringing a new tire to you.”

Reported by Paul Kurtz, KYW Newsradio