Tengzhong is known in China for making a wide range of road equipment, from bridge piers to highway construction and maintenance machinery. But even before the Hummer deal, the company had been moving more into heavy-duty trucks, including tow trucks and oil tankers.

“Over all, we’re pretty pleased,” said a Hummer spokesman, Nick Richards. “If you think about the qualities we’d want in a new owner for the brand, this buyer really met all the criteria. They’ve got a proven track record in international business, and they’ve got a long-term vision for the brand. They’ve got the capital to invest in more efficient vehicles, which is what’s necessary to grow the brand.”

If the deal is completed, it would be the first acquisition of a well-known American auto brand by a Chinese company, after many months of speculation about such a deal. Chinese automakers have already purchased the MG and Rover brands, two of the most famous names in British automotive history.

As a Chinese company, Tengzhong could face a challenge in presenting the deal to American Hummer owners. The brand has long sought to emphasize patriotism, stressing that the Hummer H1 was essentially the same vehicle built in the same factory as the Humvee that carries American soldiers into battle in Iraq and elsewhere.

It was Gov. Arnold Schwarzenegger of California who persuaded the longtime maker of Humvees, A. M. General in Mishawaka, Ind., to build a civilian version. As he recounted at a Hummer news conference in 2001, Mr. Schwarzenegger was filming the movie “Kindergarten Cop” in Oregon in 1990 when he saw a convoy of 50 Humvees drive by and decided that he had to have a civilian model of the same vehicle, which became the Hummer H1.

G.M. bought the rights to the Hummer brand in 1999 and began making somewhat smaller Hummers. G.M. initially procured the H1 from A. M. General, but discontinued the model in 2006.

Under the preliminary agreement announced on Tuesday, G.M. will initially continue to manufacture Hummers under contract for Tengzhong, which will then market them around the world. G.M. will continue making the H3 and H3T models in Shreveport, La., through the end of next year and the company said it might enter into a long-term agreement to build Hummers and important parts for Tengzhong.