Gary Cowger was months into a stint as chairman of General Motors’ Adam Opel unit in Germany in 1998 when GM Chairman Jack Smith tapped him to be the company’s top labor negotiator.

A costly and bitter UAW strike in Flint, Mich., recently had ended and Cowger brought in Mary Barra — then an executive assistant to Smith — to lead internal communications. Cowger would be Barra’s boss and mentor for nearly a decade.

“It was clear she had the intellect and the interpersonal skills that we needed during a pretty tense time,” Cowger said in late 2013, shortly before Barra took over as the first female CEO of a global automaker.

Cowger, a former president of GM North America, died Feb. 17 at his home near Dallas. He was 75.

Cowger had battled cancer for two years before his death, Judy DeMars, his former secretary at GM, told Automotive News.

He retired from GM in 2009, almost 45 years after being hired as a co-op student in his home state of Kansas. Cowger was president of GM North America from 2001 to 2005, then head of global manufacturing and labor relations until he retired four years later.

In that role, he oversaw an effort to build small cars profitably in the U.S. and negotiated major concessions with the UAW ahead of the company’s 2009 bankruptcy filing. Those deals helped pave the way for the emergence of New GM shortly before Cowger retired.

“I was deeply saddened to hear the news of the passing of Gary Cowger,” Barra said in a statement. “Gary made countless contributions to GM. He was an influential leader and mentor to me and so many others. My thoughts are with his family and loved ones during this difficult time.”

In high school, Cowger had aspired to play baseball at Kansas State University, but a counselor suggested he look into GM’s nearby Fairfax assembly plant instead.

“You know, you have a lot of technical capability, and you really ought to go down and talk to General Motors,” Cowger recalled the counselor telling him.

So he enrolled in the General Motors Institute — now called Kettering University — and did co-op work at the Fairfax plant, where he molded seats and hung doors.

After earning his bachelor’s degree from GMI in 1970 and a master’s degree in management from the Massachusetts Institute of Technology in 1978, Cowger’s jobs at GM included manager of the Lordstown, Ohio, assembly complex and Cadillac’s manufacturing chief.

At the Lordstown plant, long a hotbed of labor strife, Cowger eased tensions.

“It was unheard of for a plant manager to come over there,” Jim Graham, who was president of UAW Local 1112 in Lordstown, told Automotive News in 1998. “Cowger demanded that management sit down with the union on a weekly basis. We had an open line of communication.”

In 1994, Cowger became president and managing director of GM de Mexico. In four years, he grew GM into the market leader by nearly doubling its share.

He told Automotive News in 2007 that he considered the assignment his greatest professional achievement.

As GM’s North American president, Cowger worked with Vice Chairman Bob Lutz to simplify the product development process and invigorate the company’s lineup. He gave his leadership team lapel pins with the number “29” to signify the company’s 29 percent U.S. market share target and renewed GM’s focus on building quality vehicles.

“We have to have every product be ‘gotta have,’ that you walk up to it and you want to own it,” Cowger said in 2002. “Our goal is to make every product that we put out a must-have product.”

Lindsay VanHulle contributed to this report.