Despite signs of a slowdown in the Chinese economy, General Motors posted record first-half sales in China, where GM sales now have surpassed the total number of vehicles the company sells in its home market of the United States.

GM and its Chinese joint venture partners saw sales surge by 10.6 percent during the first half of 2013, to nearly 1.6 million vehicles, an all-time record that positions it as the booming Asian nation's No. 2 automotive manufacturer. It sold just over 1.4 million vehicles in the U.S. during the same period.

GM isn't the only American maker outpacing the growth of the overall Chinese market. Rival Ford set its own record for the first half, with sales surging 47 percent there and demand up 44 percent in June.

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While several makers have yet to report their final numbers, it appears that the two American makers significantly outperformed the overall Chinese market. Passenger car sales for the first half expected to be up 14 percent, with June growth a more modest 10 percent year-over-year, according to domestic industry sources.

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