"It's a very painful process," Chief Executive Officer Fritz Henderson told The New York Times. "We don't have a lot of bad executives. We just have too many of them."
Henderson said in an interview Friday 400 of the 1,300 top executive jobs will be cut through resignation or retirement.
In recent years, thousands of GM hourly workers, foremen and office workers have been laid off and plants have closed. But executive ranks at the top were not affected.
Henderson did not give the Times much detail about his plans but he said he is being pressured to "flatten out" management structure.
One likely step is to merge the Automotive Strategy Board and the Automotive Product Board into a single smaller executive committee.
GM came out of bankruptcy Friday. But the company is now partly owned by the federal government and has received $50 billion in federal assistance.
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