More shakeup at GM. Chevy chief Dewar out.

Here goes the merry-go-round. Two more executives are heading out at General Motors. Chevrolet General Manager W.W. Brent Dewar is quitting his job, the company said. He will be replaced by longtime Chevy hand James Campbell. Separately, a management source said that Buick-GMC general manager Michael Richards is out. What does it all mean? For starters, GM better start doing some hiring, and fast. With the CEO out, the CFO soon to be replaced and one brand manager job open, GM needs to start stabilizing its management ranks. This is a pivotal point for a company that is launching new models and trying to patch up tattered brands.

With Dewar, GM loses a controversial figure within the company. Some GM managers thought he was intimidating and arrogant. Others thought he was brilliant. But he always exceeded objectives, according to one executive who oversaw Dewar’s work. To his credit, Dewar was giving other advertising agencies a crack at Chevy ad work. GM’s vitally important brand has relied on Campbell Ewald for decades. Vice Chairman Bob Lutz started bidding out the ad work, but Dewar played a key role in picking agencies for Chevy. That will fall in part on Campbell.

A source close to Dewar says that he was tight with Henderson and was dismayed at his firing. The two worked together in Brazil. Dewar did not return a phone call and an email.

In any case, Chairman and CEO Ed Whitacre has already shifted executives around and more moves are coming. Even if Whitacre finds a CEO to replace Fritz Henderson—who was ousted as CEO last week, within the next six months—there are still a few key jobs to fill. His selections will be important, and closely watched.

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