Despite slowing sales at home, GM sells 10 million cars worldwide in 2017 for the first time, lifting it to record profits thanks to China. Strong sales in China more than made up for slower sales in the United States. The milestone led GM, the largest American automaker, to record profit. General Motors Co. said Thursday its sales in China rose 7.1 percent last year to set a new annual sales record in the country, its largest sales market.