The company raised 1B on Jan. 4, including 500 million from General Motors. SAN FRANCISCO -- Lyft continued a flurry of news Monday with the extension of a program that could add hundreds of thousands of drivers to its ride-hailing service. Lyft said it is expanding its short-term, car-rental service for drivers, Express Drive, to the San Francisco Bay Area, Denver and Los Angeles this year. It is currently available in Chicago, Boston, Baltimore and Washington, D.C. Lyft President John Zimmer and General Motors President Dan Ammann made the announcement before they are to discuss it later today at Fortune's Brainstorm tech conference in Aspen, Colo. In January, GM poured 500 million into Lyft to create an on-demand network of self-driving cars.