General Motors Corp. (GM) and Ford Motor Co. (F), the nation's two largest automakers, reported lower U.S. sales in 2004 despite an onslaught of new vehicles, while Asian manufacturers continued to chip away at Detroit's hold on the American automotive market.

Toyota Motor Corp. (search) and Nissan Motor Co. (search) , in particular, reported record-setting years. Toyota's U.S. arm sold more than 2 million vehicles for the first time in its 47 years of existence as its sales grew 10 percent for the year. Business in December rose 18 percent.

Nissan North America, aided by full-year sales of its full-size Titan pickup and other new vehicles, said sales rose 23.7 percent for the year and 32.7 percent in December.

"Our products have stimulated demand," said Yukitoshi Funo, president and chief executive of Toyota Motor Sales USA Inc. "The sales milestone is a reflection on the acceptance of products as varied as Scion, Sienna and Prius."

No. 1 GM said Tuesday its business declined 1.4 percent in 2004, a disappointment given its industry-leading 29 vehicle introductions. Car sales were down 3.7 percent; truck sales rose less than 1 percent.

Total sales for December fell roughly 7 percent, with losses on both the car and truck sides.

No. 2 Ford's U.S. sales fell 4.9 percent for the year and 3.6 percent in December, the 10th monthly decline of 2004.

Ford said Tuesday that sales of its Ford, Lincoln and Mercury cars rose nearly 1 percent in December, helped by late-year arrivals such as the next-generation Ford Mustang and its new flagship sedan, the Ford Five Hundred.

But truck sales fell 5 percent in December.

For the year, car sales were off 14 percent, despite Ford's much-touted "Year of the Car" promotion.

Truck sales fell slightly less than 1 percent for the year, but Ford's F-Series (search) lineup retained its position as America's best-selling vehicle for the 23rd straight year. Truck sales include pickups, vans and sport utility vehicles.

The percentages are adjusted and based on the daily sales rate. There were 27 selling days last month and 26 in December 2003. There also was one extra selling day for all of 2004 versus 2003.

Analysts have said new vehicle sales likely rebounded last month from a disappointing November, but the big winners again were expected to be the top Asian brands.