DaimlerChrysler agreed yesterday to a costly deal with Cerberus Capital Management to undo its merger with Chrysler, ending a partnership hailed nearly 10 years ago as a model of global cooperation and underscoring the shaky financial state of Detroit auto companies.

The breakup of the Daimler-Chrysler marriage poses fresh uncertainty for Chrysler's 80,000 employees. More than most buyout firms, New York-based Cerberus is noted for targeting underperforming companies or ones in bankruptcy protection — such as Air Canada and Alamo car rental — and making quick, deep cuts to workforces and overhead. Cerberus would assume control of 80 percent of the carmaker, and Daimler would retain the remaining 20 percent.

In taking the American icon, Cerberus would lift private-equity investment into the highest ranks yet of the struggling auto industry. The firm agreed to contribute $6.05 billion to Chrysler and pay Daimler $1.35 billion. But through a complicated set of transactions and other considerations, Daimler would actually end up paying about $1.5 billion to relieve itself of Chrysler. Daimler paid $36 billion for the company in 1998.

As part of the deal, Daimler also would no longer have the massive $19 billion burden of Chrysler's pension and health liabilities, which were an increasing aggravation to investors.

Despite the uncertainties, United Auto Workers President Ron Gettelfinger endorsed the deal. In a Detroit radio interview, Gettelfinger said he and another senior UAW official made a "last-ditch" appeal to Chrysler Chairman Dieter Zetsche on Saturday to keep Chrysler under the Daimler umbrella. He said Zetsche made it "absolutely clear" that Daimler holding on to Chrysler "was not an option."

Gettelfinger said Zetsche spent an hour and a half with him, going over every consideration that went into the choice of Cerberus and noting the firm's financial commitments to Chrysler. He said the UAW is scheduled to meet with Cerberus today to confirm its promises. "I want to make sure the commitments made to us along the way will be kept," Gettelfinger said.

He went out of his way to express optimism about the new arrangement: "It's time for us to get all of this behind us and move forward to make this company successful for our membership and for the shareholders. ... In fact, our goal now will be to prove that Daimler made a mistake because we're going to make this thing successful."

John W. Snow, former U.S. Treasury secretary and chairman of Cerberus, also took to the Detroit radio waves yesterday to promote the Chrysler deal.

"We want to be part of restoring Chrysler to the front ranks of the auto industry, where it belongs," Snow said. He promised to maintain good labor relations and to shield Chrysler managers from the scrutiny of Wall Street, giving the automaker room to make a new start. "The great name of Chrysler is coming home," Snow said.

But the question raised throughout the industry yesterday is what a new Chrysler might look like. Aaron Devers, a 46-year-old repairman at Chrysler's Sterling Heights assembly plant, near Detroit, said worker morale was low yesterday. He said plant workers expect more job cuts.

"We already know we are under the hatchet," Devers said. "This particular company has a reputation for that."

Salespeople at a Chrysler-Jeep dealership in Gaithersburg, Md., were confused about the deal, said sales manager Greg Lewis. Chrysler's corporate office sent over a six-page explainer document with 34 questions. Among them: "Why is Cerberus purchasing Chrysler? What does Chrysler have to gain? Who is Cerberus Capital Management?"

Private equity's entrance into the U.S. auto industry is part of the historic changes forced on the automakers by increasingly hard times, said David Cole, chairman of the Center for Automotive Research.

"You just can't escape the fact that we're in a transformational period," Cole said. "The old way is not survivable. Investors, managers and labor all have accepted that big things have to be done."

Among the many factors that led to this milestone was the diminishing clout of organized labor in the auto industry. Labor historian Nelson Lichtenstein of the University of California at Santa Barbara said Gettelfinger — who once vocally opposed the entrance of private equity into the U.S. auto industry — had little choice but to go along with the Cerberus purchase because of the UAW's inability to organize foreign automakers in the United States.