Consumer alert: One-third of new cars don't carry a spare tire

AAA research shows substitute inflator kits are expensive and can leave motorists stranded

Automakers' decision to remove spare tires on new cars to meet tougher federal fuel standards has left more than 30 million drivers stranded, according to new AAA research.

Expensive tire inflator kits that have replaced the spare tire in millions of vehicles over the past decade have limited functionality, AAA says, and cannot provide even a temporary fix for many common tire-related problems.

AAA’s tests of the most common tire inflator kits found that while the units worked well in some scenarios, they are not a substitute for a spare tire. For an inflator kit to work effectively, a tire must be punctured in the tread surface and the object must remain in the tire. Used correctly, the kit coats the inner wall of the tire with a sealant and a compressor re-inflates the tire.

But if the puncture-causing object is no longer in the tire, or if the sidewall is damaged or a blowout has occurred, a tire inflator kit cannot remedy the situation and the vehicle will require a tow.

“Flat tires are not a disappearing problem, but spare tires are,” said John Nielsen, AAA’s managing director for automotive engineering and repair.

Despite advances in vehicle technology, Nielsen said, AAA has not seen a decline in the four million annual tire-related requests from its members in the last five years.

For consumers, the consequences of not having a spare tire on board can be costly. Each four-pound inflator kit eliminates approximately 30 pounds of tire weight, resulting in minimal savings in fuel consumption. But at a cost of $300 per use, the kits can hit consumer pocketbooks up to 10 times harder than a simple tire repair. In addition, the shelf life for a kit is only four to eight years.

Fewer vehicles each year carry spares. Along with run-flat tires, tire inflator kits have taken the place of spare tires on 29 million vehicles in the last 10 model years, steadily increasing from 5 percent of 2006 model year vehicles to more than one in three current model year vehicles.