What could be missing from your trunk

You're driving along when you hear the thump, thump of a flat tire. You go back to get the spare tire only to discover your car didn't come with one.That's not a mistake. In a quest to cut weight and boost gas mileage, about one-third of new cars come without a spare tire, according to AAA. And this has been true since the late 1990s.Lack of a spare can turn an annoying loss of a few hours into schedule-busting loss of a whole day. Instead of a quick tire change by the crew from roadside assista