General Motors Corp. has closed its last solely owned Dayton-area plant. But Dayton is still very much tied to the auto industry, off-shore and domestic.

Honda, Delphi, Tenneco, Harco Industries, Behr Thermal Products, Inteva Products and, yes, a jointly owned GM-Isuzu operation all continue to produce locally.

There are others, as well. And those companies rely on suppliers and vendors, many of them local.

"We are a community that manufactures and makes things," said Joe Tuss, assistant Montgomery County administrator. "Automotive will be a part of it, but it will be more diversified."

"I do not believe we will build our economy on just one industry," said Deborah Feldman, county administrator.

Manufacturing will be always be critical, but so will finding "diversity" within manufacturing, Feldman added.

This is a tough time for auto companies. Firms still standing remain vulnerable to the worst economic slowdown in decades. Even Honda has announced at least two production slowdowns — but no layoffs — this year at its Marysville and East Liberty plants.

GM still operates its DMAX plant, owned with Isuzu Motors, off Dryden Road in Moraine. Even after two waves of layoffs in 2008, about 435 hourly workers still make engines at DMAX for heavy-duty trucks, such as the Chevrolet Kodiak and GMC Topkick models.

And GM still is making a $69 million investment into the plant for next-generation 6.6-liter V-8 diesel engines.

In recent years, Delphi had as many as seven plants running in Montgomery County. Today, only the company's Vandalia plant continues to operate, with fewer than 200 workers. (Located near the plant off Northwoods Boulevard is a Delphi engineering office. A Delphi spokesman could not give total Vandalia employee numbers.)

Still, other companies have put manufacturing work in at least two former Delphi plants. Before recent layoffs, Tenneco employed about 300 workers at what was Delphi's Woodman Drive plant. Delphi leased part of the Woodman facility — about 930,000 square feet — to Tenneco earlier this year.

And in August, Harco Industries announced a lease to occupy the former Delphi plant at 3535 Kettering Blvd., in the shadow of the GM assembly plant where production ended Dec. 23. With some 350 workers, Harco produces brake hoses and brake hose fittings there.

Honda is the only company actually assembling automobiles anywhere near Dayton. The company has nearly 12,000 employees within a 75-minute drive of Dayton, including nearly 400 workers at a Troy distribution site.

"There is no doubt that automotive manufacturing and automotive parts manufacturing, from a supplier perspective, is still going to be a strong part of both the Dayton regional economy as well the Ohio economy," Tuss said.

Contact this reporter at (937) 225-2390 or tgnau@DaytonDaily

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