Ford workers across the country have voted in favor of a new four-year contract.

The United Auto Workers union said late Friday that the contract passed with a 51.4 percent vote.

The agreement covers 53,000 U.S. hourly workers at 22 plants, including roughly 9,400 workers at Ford’s two Louisville plants. The contract raises wages for all workers, provides an $8,500 signing bonus and promises $9 billion in investments at Ford’s U.S. plants over four years.

Those investments include $1.3 billion at the Louisville Assembly Plant and Kentucky Truck Plant.

Ford’s union workers in Louisville rejected the contract with more than 60 percent voting against it earlier this week. In an interview with WFPL News on Friday, UAW Local 862 President Todd Dunn said a variety of issues contributed to the workers’ vote.

In interviews with other Louisville media, workers cited concerns about the deal’s terms for legacy employees and said Ford had yet to make workers whole after concessions driven by the recession.

Ford said it was pleased with the vote. It said the contract helps the company, employees and their communities.

Ford’s contract was the last of the Detroit automakers to win approval. Fiat Chrysler workers approved their contract in October, while the union said earlier Friday that General Motors’ contract was approved.

Featured image of Louisville Assembly Plant from Google Maps.