A major supplier to the commercial truck industry through its Spicer brand, Dana Holding Corp. has been using advanced gear technology to boost powertrain efficiency.
Most trucks run their engines at about 1,450rpm while cruising, with diesel powertrains producing about 200hp. By lowering the engine to 1,100rpm, while still maintaining 200hp, trucks can save about 550 gallons of fuel per year. However, that strategy puts a lot more strain on powertrain components, says Ryan Laskey, vice president of commercial vehicle engineering and quality.
“We’ve always held that the best way to spec a driveline is by selecting components that have been carefully engineered, thoroughly tested, and proven to deliver the performance and durability you need,” Laskey says.
To support downspeeding, he says Dana designed a tougher primary gear for the truck tandem axle. Wider-face gearing with longer tooth lengths reduce contact and bend stress in the axles, and a rigid ring-gear mounting eliminates joint loosening. Those improvements – along with computer controls; upgrades to input shafts, input bearings, pinion splines, and pinion bearings; and faster gear ratios – allow a system that improves truck fuel economy while maintaining component durability.
“For every 100rpm drop in engine speed, torque goes up significantly to maintain full power,” Laskey says. He adds that with the right designs, gearing systems, and controls, engine speed reductions are possible.
Dana Holding Corp.