Mack Adds Drive-Axle Production to Maryland Plant's Integration Strategy

HAGERSTOWN, Md. — Mack Trucks introduced its new drive-axle line here, the result of a two-year, $30 million investment that is part of the company’s strategy of vertical integration of powertrain components — engines, transmissions and axles — that are all made in-house.

“Bringing axle production to Hagerstown allows us to oversee the manufacturing process — from design to assembly — and deliver the high-quality components our customers depend on,” company President Stephen Roy said at an Oct. 13 plant event. “Building Mack engines, transmissions and now axles under one roof also demonstrates our continued commitment to integrated powertrain design.”

The company’s axles are now standard on most of its trucks, although Mack still offers axles from vendors such as Dana Holding Corp. and Meritor Inc. as options.

The importance of optimizing the interaction between engines and transmissions has been strongly endorsed, both by truck makers and independent component manufacturers such as Cummins Inc. and Eaton Corp. Axles are the next logical step in the chain, Mack marketing manager Stuart Russoli said.

“A lot of this is rear-axle ratios . . . they play a role,” Russoli said. The ratios measure how many turns of the driveshaft are needed to roll the truck’s wheels one complete turn.

The company’s engineers currently like ratios between 2.6- and 2.8-to-1 for Pinnacle highway tractors, while vocational axles remain above 3-to-1.

The ratios are planned with precision for each application and tractor, Russoli said, adding that the process is easier when all three major powertrain components are designed and built in-house.

The company places a “gold” bulldog hood ornament (actually made of brass) on Macks containing the full proprietary powertrain.

Mack, based in Greensboro, North Carolina, is part of the Volvo Group. The plant here assembles engines and transmissions for Mack and its sister company, Volvo Trucks, as well as Mack axles.

Production workers are represented by the United Auto Workers.