DETROIT (AP) -- When Ed Whitacre Jr. took over as General Motors Co.'s CEO in December, he told reporters that executives wouldn't have long to show results.
He meant it.
GM announced sweeping changes in its sales and marketing operations on Tuesday, splitting the two functions after Whitacre combined them in December and shuffling executives across the company's operations.
Susan Docherty, formerly vice president of U.S. sales and marketing, will now head only marketing, and Steve Carlisle, who ran GM's Southeast Asia operations, was named vice president of U.S. sales.
Both will report to North American President Mark Reuss, who said the move eliminates a layer of management between him and the customer.
He said the structure will allow people to focus exclusively on dealers and sales, while others will focus on marketing.
He said there was dissatisfaction with GM's results in the past three months, although there were good things like sales staying on par with the industry despite shedding four brands, Hummer, Saturn, Pontiac and Saab.
"We have got to accelerate success in North America," Reuss told reporters on a conference call. "I don't think we've moved far enough fast enough."
At Chevrolet, the company's largest brand, GM kept general manager Jim Campbell as marketing chief and added Alan Batey to head sales and service. He most recently was president of GM's Holden operations in Australia.
At Cadillac, general manager Bryan Nesbitt will go back to the design studio. He'll be replaced by Don Butler, who will be in charge of marketing, and Kurt McNeil. Butler rejoined the company from Inrix, a Kirkland, Wash.-based traffic research firm, while McNeil was previously general sales manager of Chevrolet.
Buick-GMC general manager Brian Sweeney stays on in charge of sales and service, while John Schwegman becomes head of marketing. He had been Chevrolet product marketing director.
In making changes in December, Whitacre told reporters in a Webcast that new executives didn't have long to show results.