How Many Gears Is Too Many? General Motors Says Nine Is Enough, Or Ten, Or Maybe More

We moved past three on the tree. We’ve long since bid farewell to four on the floor. The ZF six-speed automatic transmission that helped to make the 2001 BMW 7 Series seem so forward-thinking at the dawn of the millennium was usurped by a seven-speed unit from Mercedes-Benz a couple of years later, and then by the Lexus LS’s eight-speed automatic in 2007.

Nine-speed automatics are all over the place: in the 2017 Acura MDX I’m driving this week, in numerous Fiat Chrysler Automobiles products, and in ten General Motors models by the end of 2017. Now the most popular line of vehicles in North America, the Ford F-Series, is arriving at dealers near you with ten-speed automatic transmissions.

But when is enough enough? How many gears is too many? Are there diminishing returns as the number of gears in an automatic transmission increases?

GM says nine is enough. Okay, ten is plenty if you insist. Ah, whatever, maybe more would be wonderful.

GM’s new nine-speed automatic first appears in the 2017 Chevrolet Malibu, then the diesel-powered 2017 Chevrolet Cruze, and then the already-revealed 2018 Chevrolet Equinox — all front-wheel-drive foundations. The ten-speed unit, with which GM and Ford also shared development, is intended for rear-wheel-drive applications.

Yet, when speaking with Wards Auto, GM’s executive director for transmission and electrification hardware engineering Chris Meagher said, “We don’t see the benefit of going higher than 10 forward speeds.”

But could more gears be possible? Acknowledging that the idea of nine and ten-speed automatics seemed unimaginable a decade ago, “You never really know for sure,” GM’s Meagher said.

While these seven, eight, nine, and now ten-speed automatics have certainly made their way into the public consciousness, Wards says six-speed automatics accounted for 55 percent of all new vehicles sold in the United States in the 2016 model year.

That percentage could fall fast, however, as ten-speed automatics become common in the most popular vehicles in America: pickup trucks.

[Images: General Motors, Ford]

Timothy Cain is the founder of GoodCarBadCar.net, which obsesses over the free and frequent publication of U.S. and Canadian auto sales figures. Follow on Twitter @goodcarbadcar and on Facebook.