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 GM's famously insular culture -- at times as bureaucratic as the government's -- to make the company more competitive. If the effort fails, the Treasury may never recoup the $50 billion it has provided GM. 'Addressing cultural issues is just as fundamental to our assignment as addressing the balance sheet or financing,' said Steven Rattner, the lead adviser to the White House on the automobile industry. In just one example, whenever a top GM executive was called to appear before lawmakers in Washington, staffers would prepare a briefing binder as thick as a big-city phonebook and hold multiple meetings to strategize over five minutes of testimony (Fritz Henderson, the new chief executive, has told employees to stop doing that). In a Senate hearing Wednesday, Ron Bloom, another adviser on the auto task force, also talked about the need for GM to break longstanding habits that have made the company, with its bloated structure, lose a step to more nimble competitors. 'General Motors has been kicking problems down the road for a long time,' Bloom said. Rattner and other government officials have repeatedly said they have no interest in running the company day-to-day. But they are taking a keen interest in shaping the new leadership team. For example, Rattner himself was behind the appointment Tuesday of Edward E. Whitacre, the former chief executive at AT&T, to become GM's new chairman. Four more vacancies on the board also have to be filled. The newcomers' primary task will be to make sure that GM rewires the corporate DNA that led to a decades-long slide in market share and tens of billions of dollars in losses. Rattner said he expects no less than the kind of wholesale restructuring that Jack Welch engineered at General Electric in the 1980s, where he earned the label Neutron Jack for decisively shedding businesses, cutting costs and jobs, and demanding better performance. The government, which has said it would not invest any more money in GM, cannot settle for anything less, Rattner said in an interview. 'We're not going to fail,' he added. 'This is too important a company.' If GM's history is any guide, outsiders can have trouble making a difference. For a quarter century, a parade of executives and activist investors, including Ross Perot, billionaire Kirk Kerkorian and his adviser, restructuring expert Jerome B. York, has failed to shake thing up at the highest level. Those brought into the company to help invigorate it, like Ron Zarella, the Bausch & Lomb executive who ran its marketing, and Chicago attorney Elmer Johnson, who held a top executive job at GM, ultimately left the company. In a famous memo that circulated in Detroit during the late 1980s, Johnson, once considered a candidate to become GM chief executive, complained that the company was hampered by its inability to execute. 'Teamwork has been replaced by Balkanization,' he wrote. 'Our culture discourages open, frank debate among GM executives in the pursuit of problem resolution.' Even within hours of seeking bankruptcy protection on June 1, the company demonstrated old habits that seemed out of sync with its new, humbled circumstances. GM's chief financial officer, Ray Young, told reporters that as a 'privately held company,' GM was not required to regularly disclose details on its financial performance - even though its new owners were in fact U.S. and Canadian taxpayers, the United Automobile Workers union and GM its bondholders. After Canadian officials and taxpayer advocates protested, GM retreated a day later, promising to make regular disclosures. Through the years, outsiders and even company insiders have complained about simple decisions, like making design changes to a bumper or headlights, requiring months of study. Government officials are vetting new board members who will join Whitacre, who readily admits that he has no automotive industry experience, in providing oversight of Henderson, who replaced Wagoner when he was forced to resign by the Treasury in March. Henderson must now prove that he can make good on his promise to make GM leaner and faster. Government officials decided to give him the title of chief executive, rather than interim CEO, in order to reassure GM troops who were rattled by Wagoner's abrupt departure. Historically, GM's senior leadership group, made up of about 100 senior managers, met in person four times a year. Since taking over on March 30, Henderson has held three conference calls with the group, in which he has stressed the need for change and pushed managers to speed up decision making, said GM's chief spokesman, Steven J. Harris. Several GM working groups have been assembled to look at the organization and eliminate time-wasting practices, he said. Henderson is leading by example. Upon receiving memos from Harris proposing action on various matters, he has told him not to send similar notes in the future, but only to provide an informational copy once a decision has been made. Harris said he disagreed that GM's board had refrained from scrutinizing company activities, as government officials have implied in their public comments. 'They just had a different take on things,' Harris said. 'We understand that this is a new environment and that we're likely to undergo a deeper level of scrutiny. Nobody has an issue with that.' Measuring any progress in changing the culture will take time. The results, after all, will be seen in the new vehicles that the company develops and produces -- and whether they reflect world-class business practices that are required to win against the best of its global competitors. 'It's not uncomplicated,' said Rattner. 'We hope and believe that it can take place.' 