A Cadillac SRX poses in front of Shanghai's skyline. The SRX has recently been one of GM's star performers in China. Sales were up 54% in March. Source: General Motors Co.

The last few weeks haven't exactly been great ones for General Motors (GM 5.31%). But GM did get some good news this week -- or at least, some not-bad news.

GM said this week that its sales in China -- now the world's, and GM's, largest auto market -- were up about 8% in March, a little behind the overall market's 9% gain.

That's not exactly spectacular, but it's not bad. As Fool contributor John Rosevear explains in this video, GM has a few things going for it in China right now -- starting with the Buick and Cadillac brands.

A transcript of the video is below.

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John Rosevear: Hey Fools, it's John Rosevear, senior auto analyst for Fool.com. General Motors hasn't exactly had a lot to celebrate recently, but the company released its first-quarter sales numbers for China this past week, and they're not bad.

GM said that its sales in China rose 7.8% in March, and 12.6% for the first quarter. GM and its joint venture partners sold just over 900,000 vehicles in China in the first quarter, which is a record for GM.

A lot of that growth came from Buick and Cadillac. Buick is a very well-established brand in China with a long long history, the last Chinese emperor drove a Buick, and it has always done well. Buick offers a big range of cars in China, but its mainstay is a model called the Excelle, which comes in three flavors.

The original one is an older model based on an old Daewoo design, it's sold as an affordable premium compact, and then there's the Excelle XT hatchback and the Excelle GT sedan, which aren't mechanically related to the original Excelle, but are closely related to the Buick Verano sold here in the U.S., although they sell way more of the Excelles in China than they do Veranos here in the U.S.; it's about a 7 to 1 difference. Anyway, all of the Excelle versions are big sellers for GM in China, and they're still growing -- sales of the Excelle GT and XT were up 38% in March.

GM is also doing well in China with the Regal, which sold over 8,600 units in March. That's over three times as many as GM sold here in the U.S. If you're getting the impression that Buick is a big deal in China, you're right, and overall Buick sales were up about 14% in the first quarter.

Chevy also does well, but until recently, Cadillac didn't have much of a presence. GM has put some effort into changing that over the last couple of years, and it's paying off. Cadillac sales in China were up 44% in March and up over 100% for the quarter, with the strong sellers being the big XTS sedan, which was introduced in China early last year, and the SRX crossover.

Luxury crossovers and SUVs are white-hot in China right now. GM is still a minor player in that corner of the market, but they're working on changing that -- SRX sales were up 54% in March, so something's going right.

We don't know yet if GM out-sold Volkswagen Group (VWAGY 0.59%) in China in the first quarter, VW has released quarterly sales totals for some of its brands, but as of right now, they haven't released a combined number for the whole group for China, but if I had to guess, I'd guess that GM will come in a little behind VW for the quarter. GM of course led the China market in total sales for years until VW squeaked past them last year, but GM continues to put up solid sales numbers, and both GM and VW remain far ahead of everybody else. Thanks for watching.