Volvo, owned by China's Zhejiang Geely Holding Group Co., began producing the S60L at its new plant in Chengdu, China, in October and is ramping up to full capacity of 120,000 vehicles annually.

"The S60L will be a relatively low volume car, [but] its significance can't be overstated," said AutoPacific analyst Ed Kim. Volvo will "use it as a testbed of sorts to ascertain both real world quality of a Chinese-built car in the U.S. and consumer reaction to it."

The S60 -- by far the brand's best-selling vehicle in the U.S. -- is produced in Sweden. The S60L, built only in China, has a wheelbase extended by 3.2 inches to 112.5 inches.

Cost is a key reason for importing the S60L from China rather than Sweden, Samuelsson said. Production in China is less costly, and the country's currency is tied to the dollar rather than the euro, which, he said, "gives more stability."

Some observers predicted an onslaught of low-priced Chinese cars in the United States by now. Honda sells China-built Fits in Canada, and some small companies have sold a handful of Chinese vehicles in the United States. But the S60L would be the first sold in the U.S. by an established automaker.

Samuelsson, who declined to discuss volume levels, said Volvo has absorbed lessons about designing large sedans in China, where more affluent owners prefer to sit in the back. In the future, he said, Volvo's large vehicles will be designed mainly for the United States and China.

"The next time we present a car you will be surprised," Samuelsson said. "We will take a big step forward in the sedan."

That vehicle, due late next year, is expected to replace the S80 sedan.