'Tis the season for new car models. Fall is when the automakers start rolling out their offerings for the next year. All-new models arrive, redesigns hit the dealerships, and updates to existing cars appear. But obviously, there's a wrinkle this time round: Both General Motors and Chrysler are fresh off bankruptcy. And you'd be right to assume there's extra pressure on their new wheels.

Chrysler, unfortunately, doesn't have much new stuff to sell. But GM has a new SUV, the GMC Terrain, that is already a sales leader and recalls a vehicle that still horrifies carmakers and critics alike. That car is the despised Pontiac Aztek, an almost universally loathed vehicle that established the paradigm for the Terrain: the crossover SUV, a half-car, half-truck concoction that is one of the fastest-growing vehicle categories. GM needs to remember the Aztek, because it represents the kind of risk-taking design that the post-bankruptcy firm will need to go forward. The temptation for the New General will be to copy successful market formulas, rather than try to define new market segments.

The Aztek, introduced in 2001, was an attempt to do something entirely different. It was aimed at then-twenty- and thirtysomethings who liked to hike, camp, mountain bike, and generally participate in the whole suite of Outside magazine diversions, but who might also want a young-family hauler with a bit more flash than your typical truck or SUV. So the Aztek came furnished with a host of outdoorsy options, an interior that could be configured according to the recreational preferences of customers, and an all-wheel-drive system for the snow and the mud and the slush and the rain. The design was boldly idiosyncratic, but GM figured it would attract buyers. It wound up scaring them, but at least it took no prisoners.

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It's easy to berate GM for always failing to see where the market is going. But in this instance it was the first to recognize the need for a new kind of vehicle to fill the crossover segment, which would grow rapidly in subsequent years. A crossover is basically a 21st-century station wagon. SUVs are usually built on the same platform used for trucks -- and they often feel that way when you drive them. They also inhale gas. Crossovers, by contrast, are built on platforms used for cars, so they have better road manners, and they're more fuel-efficient. There were some crossover-ish vehicles before the Aztek, such as the Subaru Forester, but these were seen as neo-wagons, or small/compact SUVs. With the Aztek, GM created something that had SUV size, minus the SUV stigma.