SAN FRANCISCO (KGO) -- When's the last time you checked the well of your trunk? It's widely assumed there's a spare tire there. But that's not always the case these days, and it's catching some drivers by surprise.
"It was a rude awakening," said Ford owner Marti Scholl, who made the discovery when she had a flat tire recently. "It seems like a safety risk. And by the way, my Ford dealer quoted a price to buy a spare from them of approximately $485 including tax."
In the Bay Area, AAA has responded to 47,000 tire calls so far this year. One in five of those drivers didn't have a spare.
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"It's definitely a surprise for those who call for a tow or need assistance and realize they don't have a spare tire in their vehicle," said AAA spokesman Sergio Avila.
That means the vehicle will need to be towed. Spares have gone away as automakers try to boost fuel efficiency by reducing vehicle weight. In their place, they've put a small inflator kit. Check them periodically, though, because they do expire.
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Some vehicles, including many luxury models, are equipped with run flat tires that have stronger side walls, which can hold up for a short time with little or no air.
"I think the answer for most people is that if you have run flat tires, they're pretty good, keeping under 50 miles an hour to get to the next place," said automotive editor Brian Douglas. He suggests using that empty trunk well to hold a spare, but the added weight could impact your fuel economy.
"Most of these spare tires do consume space and weight," noted Tony Rivero, assistant manager at Bruce's Tire in San Jose. "You have the jack, you have the spare that you have to contend with."
One interesting note: AAA reports electric vehicles top its list for not having a spare tire.