Downtown Detroit GM Hedquarters

General Motors Co. (GM) has agreed to invest $500 million in Lyft Inc., boosting the on-demand ride startup’s valuation to $5.5 billion. The move makes GM a serious ally for Lyft, who faces increasing competition from Uber Technologies Inc.

GM’s investment was a part of a $1 billion financing round for Lyft, and the company’s $500 billion contribution marks the largest investment by an automaker in the rapidly-growing ride-hailing industry.

Lyft and GM stated that they will work together to create a fleet of self-driving cars that riders can call on-demand. In the immediate future, General Motors will offer vehicles to Lyft drivers for short-term rent in various hubs throughout the U.S.

Dan Ammann, GM President, will be joining Lyft’s board as part of the deal and expects that the auto industry will change more in the next five years than in the last 50.

Ride-sharing is a growing industry, and other automakers are attempting to get in on the ground floor while the sector is still in its infancy. Ford Motor Co. (F) is toying with the idea in London, where the automaker launched a network of shared cars.

The latest financing round for Lyft nearly doubles the startup’s total financing. Over the last three years, the company has raised over $2 billion. Lyft’s current valuation of $5.5 billion includes value from its latest $1 billion round of financing.