The Chevrolet Malibu and the Mazda CX-9 were chosen as the car and truck of the year at the North American International Auto Show.
The awards were presented Sunday, the first day of media previews for the show. It opens to the public on Saturday.
Click here to view photos from the Detroit Auto Show 2008.
It was the second major award for the CX-9 crossover, which was named Motor Trend's 2008 sport utility of the year in October.
"The CX-9 was designed for North America, and I think the award is recognition that the team delivered on the promise," Mazda Executive Vice President Robert Graziano said.
Bob Lutz, General Motors Corp.'s vice chairman of product development, said GM is rapidly trying to add more production capacity to keep up with demand for the Malibu.
"It's gone way beyond our expectations," he said.
Four of the six finalists for the awards were GM products.
The Malibu, Cadillac CTS and Honda Accord were finalists for car of the year, while the CX-9, the Buick Enclave and Chevrolet Tahoe Hybrid were finalists for truck of the year.
GM was a double winner in 2007, while Honda Motor Co. captured both honors the year before.
To be considered for the coveted honor, which often is used in automakers' advertising, vehicles must be new or substantially changed from the previous model. More than 50 new vehicles were eligible this year, but jurors winnowed that list to 15 cars and 13 trucks.
The winners were selected by a jury of 46 automotive journalists from the United States and Canada. Jurors consider a variety of factors, including innovation, design, safety, handling, driver satisfaction and value.
The North American honors have been given annually since 1994.