DMAX plant overcomes odds that others couldn’t

Beginning today, the Moraine plant begins production of new diesel engine,

The DMAX engine plant has endured the worst economic downturn since the Great Depression, the largest industrial bankruptcy in history, gas price fluctuations and changing consumer tastes that sunk far larger plants and closed better known companies.

But DMAX — maker of the famed Duramax diesel engine for big trucks — is still here.

The Moraine plant has not only survived, it thrives, being rewarded recently by owners General Motors and Isuzu with a newly designed diesel engine and increased capacity.

For plant manager Matt Gross and more than 600 fellow employees, the moment is sweet.

“You got to have the right product, you got to have the right process and you have to have the right people,” Gross said.

Working ‘as a family’

The new engine — first announced by plant co-owner General Motors in late September — is a new lease on life and confirmation that the plant is part of GM’s future.

Beginning today, the Dryden Road plant will make a redesigned Duramax 6.6-liter V-8 turbo-diesel which will be offered on the 2017 Chevrolet Silverado HD.

“That new engine looks to be a home run for them,” said Mark Williams, editor at and assistant managing editor at

In his web site’s head-to-head pickup comparisons, conducted by truck “experts,” the Duramax repeatedly emerges as a winning power-plant, going up against trucks with Cummins engines and the Ford Powerstroke.

The engine is just one facet of recent good news for DMAX. In December 2015, plant co-owners GM and Japanese truck maker Isuzu said they will invest $82 million into the facility to enable the production of even more engines.

While GM did not offer numbers on how many more engines the plant will produce after the investment, the automaker did say 150 new workers would be hired as part of the production ramp-up.

“It’s reassuring to our membership and satisfying at the same time,” said Carl Kennebrew, president of IUE-CWA Local 755, which represents nearly 500 hourly DMAX workers. “We have a different culture here, and I think that’s a testament as to why we continue to survive.”

Crisis after crisis — recession, bankruptcy, lingering uncertainty — “caused us to work together as a family,” Kennebrew said.

But it’s up to the company to go to market with an engine that meets “world class” standards, the plant manager said.

“Is it a guarantee?” Gross asked. “No. We work in the automotive industry, and you don’t get guarantees. You earn work.”

‘They wanted to keep DMAX’

The DMAX plant was built during a more optimistic time, the late 1990s, when the national economy was stronger and American manufacturing was generally under less pressure from global trade.

Consider that in the Miami Valley alone, Delphi had about 15,000 workers at the time. Today, the company has none locally.

GM wanted to keep pace with strong competition in the heavy-duty diesel engine market, where it lagged at the time.

GM and Isuzu — a Japanese company then building its own diesel engine — decided to team up, choosing Moraine as the home of a new 650,000-square-foot plant. The site was a stone’s throw from GM’s light truck and SUV assembly plant just across Ohio 741, also in Moraine.

The first production Duramax engine rolled off the line on July 17, 2001.

Ensuring years were challenging. In December 2008, the nearby GM assembly plant was shuttered. Around GM’s 2009 bankruptcy, employment at the DMAX plant was cut by about half. Layoff notices were coming from many Dayton-area companies, not just DMAX.

Mike Davis, development director for the city of Moraine, remembers the time well. For a while, GM spokespeople declined to comment on the plant’s future, and no one knew if it had a future.

But DMAX had something going for it: It was unique, Davis said. DMAX is the only heavy-duty diesel truck engine plant under the GM umbrella.

“Really, the story is that even GM itself and Isuzu saw that, back during the GM bankruptcy,” he said. “They wanted to keep DMAX as part of their portfolio under the new GM umbrella.”

“DMAX is successful partly because it stands on its own,” he added.

How did it survive when other plants didn’t?

One answer: The DMAX plant was able to land new products — assignments for updated engines — while the other Moraine GM plant never was able to secure a new SUV model.

“They (DMAX) make a product that (other engine builders) can’t match,” Davis said. “I think that’s gone a long way toward their sustainability … they continue to lead the field.”

‘A milestone day’

Oct. 6 was the final day of production for the model year 2016 6.6-liter Duramax engine, known to the DMAX workforce by its manufacturing code, the “LML.”

“It is a milestone day,” Gross said in an interview that day. “The next 36 hours for us are about emptying out our entire system so we can do all of our equipment conversion.”

Today, production of the new engine starts.

Shinichi Suzuki, president, chief executive and chief operating officer of DMAX, has been savoring the moment. The current Duramax powerplant was so well designed, that engineers weren’t certain how to improve on it, he said.

“We thought we can’t improve the power source so significantly,” the CEO said. “But now, the engine, the next model, is greatly improved — far more than we expected or far more than we estimated.”

The engine has been boosted from 395 to 445 horsepower, he and Gross said. GM said it boasts a 19 percent boost in max torque over the current Duramax, the performance is quieter and smoother with engine idle noise reduced 38 percent.

“A big surprise for me, the engine we will manufacture is completely changed from the current one, but still we can produce it on this (plant) floor,” Suzuki said. “That is amazing.”

Jim Clark, president of the IUE-CWA, said the DMAX plant has a number of strengths working in its favor. But he singled out one: What he called the “lost art” of employers and employees simply getting along. He said DMAX workers understand the market and adapt.

“One side can’t do it alone,” Clark said.


Ownership: GM-60 percent; Isuzu Diesel Services of America Inc.-40 percent.

Employees: 490 direct hourly employees, 115 direct salaried, not including contractors or third-party workers.

First production engine: July 17, 2001

One millionth engine: April 16, 2007

Prior engine's horsepower: About 395.

New engine's horsepower: 445.

Year opened: 1999.

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