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February 28, 2016 4:00 PM, EST

NASHVILLE, Tenn. — Dana Holding Corp. announced improvements to its truck axles and driveshafts to help truck makers meet tighter federal standards on greenhouse-gas emissions.

Steve Slesinski, a Dana director for commercial vehicle driveline planning, said here Feb. 28 that for every 100 rpm engine speed decreases, fuel efficiency increases by 1%.

As engine and transmission makers emphasize downspeeding, or running a truck’s engine at lower revolutions per minute to boost fuel economy, that creates a need for faster axles with lower ratios.

The Dana event was part of the annual meeting of American Trucking Associations’ Technology & Maintenance Council. Slesinski said the Dana axles have a ratio of about 2.5-to-1 and are designed for use with the Cummins Inc.-Eaton Corp. SmartAdvantage engine-transmission combination.

A 2.5-to-1 ratio means it takes 2.5 turns of the driveshaft to get one revolution out of a truck’s drive wheels.

Slesinski said faster axles produce more stress on driveshafts. Therefore, Dana also rolled out a new driveshaft that weighs 30 pounds less than comparable models and can better withstand the forces generated by faster axle ratios.