Wondering when the automatic gearbox arms race will end? 8 speeds? 9 speeds? Even 10 speed gearboxes have been thrown out as grist for the automotive rumor mill, but one exec apparently has the answer.
The CEO of ZF transmissions said that 9 speed gearboxes will be the zenith of transmissions – anything more will be too complex and heavy to produce any efficiency gains.
Stefan Sommer, ZF’s grand fromage told Automotive News Europe that 9 speeds is the “natural limit” for gearboxes, and anything beyond that invokes the law of diminishing returns. Chrysler is expected to be the first to adopt a 9-speed automatic, but don’t look for anything beyond that, says AN
Earlier this year, Julio Caspari, president of ZF’s North American operations, hinted that a “Can-you-top-this?” race to add gears may be driven by marketing considerations rather than fuel economy.
That’s because there is only an 11 percent gap between the most-efficient transmissions today and a theoretically perfect gearbox