DETROIT -- Fiat will set a new direction at Chrysler, which finished its tour through bankruptcy court Wednesday, completing its deal to join forces with the Italian automaker.

At Ford, a chief executive brought in from the aircraft industry is helping to shake up the company.

But it will be up to the federal government, which will own a majority of General Motors when it emerges from bankruptcy, to tackle what is perhaps the most difficult challenge in Detroit: transforming G.M.'s insular culture -- at times as bureaucratic as the government's -- to make the company more competitive, according to The New York Times.