Perhaps known simply as vans to many drivers, multipurpose vehicles are shedding their image as humble delivery vehicles as they gain in popularity and become an engine for growth in China's auto market. Their sales have surged in all three quarters of the year.

Statistics from the China Association of Automobile Manufacturers show that 820,000 MPVs were sold in the first nine months across the country, a 33 percent increase year-on-year, raising its share in the auto market to 7.6 percent for the period.

The robust growth is due in part to a change in the classification of vehicles by the association.

Since early 2013, it moved several popular models including the Wuling Hongguang and Chang'an Honor into the MPV category. Before they were calculated in the minivan segment.

The association classifies passenger vehicles into four categories: cars, SUVs, MPVs and minivans.

Minivans represent one of the best-selling segments in China due to their popularity in the vast rural areas. They sell at an affordable price to low and middle-income customers.

Like MPVs, minivans also have an interior that can be flexibly modified to accommodate passengers or cargo.

But the MPV market would still show strong growth without the change in classification. One driving force is demand for better vehicles as minivan owners turn to low-end MPVs that offer more comfort and room, said analysts. As well, many local automakers are launching more products to stimulate market demand.

Wang Lei, public relations director of the SAIC-GM-Wuling Automobile, said he is optimistic about the market potential. MPVs have historically had a 4 percent share of China's auto market, while the figure stands at around 10 percent in mature markets, which if reached would mean a about 1.3 million vehicles a year in China, he said.

While the MPVs seem to have a bright future, the minivan market has suffered a slump in sales.

Just 121,400 minivans were sold in September across the country, a 30 percent decline year-on-year, according to the association.

Minivans gained its popularity after the government initiated a series of favorable polices in 2009 to expand auto sales in rural China.

Analysts said the move had overdrawn the market demand. And consumers are looking for better products, they added.

Like the SAIC-GM-Wuling, some traditional minivan manufacturers are transforming their products into low-end MPVs and other vehicles.