Published

ZF: 9-Speed Limit for Transmission Efficiency

There is no fuel economy gain to be won by adding more than nine forward gears to an automatic transmission, declares ZF Friedrichshafen AG CEO Stefan Sommer.
#economics

Share

There is no fuel economy gain to be won by adding more than nine forward gears to an automatic transmission, declares ZF Friedrichshafen AG CEO Stefan Sommer.

He tells the Automobilwoche Congress in Berlin that the weight and complexity of more ratios would offset any further improvement in powertrain efficiency. Nevertheless, previous media reports say General Motors, Ford and Hyundai are developing 10-speed automatics.

ZF has said that its 8- and upcoming 9-speed gearboxes are 11% and 16% more efficient, respectively, than a conventional 6-speed automatic.

Julio Caspari, who heads ZF's North American unit, told Automotive News earlier this year that a "perfect" transmission would be 11% more efficient than the best gearbox currently in production. But he also inferred that adding more than nine gears may be a marketing rather than performance-driven goal.

ZF began producing an 8-speed automatic three years ago and is scheduled to launch its 9-speed gearbox in 2013. Chrysler Group will use both transmissions in its high-volume models.

RELATED CONTENT

  • On Quantum Navigation, EVs, Auto Industry Sales and more

    Sandia’s quantum navi, three things about EVs, transporting iron ore in an EV during the winter, going underwater in an EV (OK, it is a sub), state of the UK auto industry (sad), why the Big Three likes Big Vehicles, and the future of logistics.

  • China and U.S. OEMs

    When Ford announced its 3rd quarter earning on October 24, the official announcement said, in part, “Company revenue was up 3 percent year over year, with net income and company adjusted EBIT both down year over year, primarily driven by continued challenges in China.” The previous day, perhaps as a preemptive move to answer the question “If things are going poorly in China, what are you doing about it?, Ford announced that it was establishing Ford China as a stand-alone business unit.

  • Report Forecasts Huge Economic Upside for Self-Driving EVs

    Widespread adoption of autonomous electric vehicles could provide $800 billion in annual social and economic benefits in the U.S. by 2050, according to a new report.

Gardner Business Media - Strategic Business Solutions