Electric vehicles are unique for a load of reasons, at least when you compare them to their combustion-powered counterparts. For example, most gasoline cars need a transmission with six, seven, eight, or even ten ratios to efficiently deliver power and do it without burning a ton of fuel. EVs don’t need that — most rely on single-ratio transmissions to deliver their power. However, some, like the Porsche Taycan, and now, the Mercedes-Benz CLA use a two-speed unit. It’s something of a rarity in the EV world, and the reasons behind Mercedes’ decision are a fascinating look inside the process of producing a new car.
The New CLA Has A Two-Speed Gearbox
Speaking to The Drive, Christoph Starzynski, head of Mercedes-Benz’s product strategy, says the decision was driven by an unwillingness to compromise on the blend of power and efficiency the company wanted the new CLA to offer. The CLA’s power output ranges from 268 horsepower in the 250+ trim to 349 horsepower in the CLA 350 4Matic, and the company estimates range on Europe’s WLTP testing cycle to be between 479 and 492 miles depending on trim.
Mercedes says first gear is used primarily for acceleration and optimized efficiency at lower speeds, while second gear is available for cruising at higher speeds for longer periods of time. The CLA’s range figures are impressive ones, and the transmission likely has a lot to do with that. It’s no powerhouse, unlike the Taycan, which also uses a two-speed unit, but the specs help justify Mercedes’ decision-making here.
The CLA Needs Its New Transmission
According to Starzynski, the idea isn’t for the transmission to be a showpiece, with simulated shifts or the like. Instead, the benefits outweighed the cost savings Mercedes may have achieved by using a cheaper, single-speed unit: “Not having a second gear is obviously cheaper than having a second gear, if you’re looking [at it] from a purely financial perspective. No, it’s not for free.” The decision also came with some challenges. Because Mercedes didn’t want the transmission to be a showpiece, it also had to work to minimize the sensation drivers get when the car changes gears.
“You don’t [want to] have this mini-second of a moment where you feel you have no power, because every time you shift the gear there’s a shortage of power somehow, even on an EV. So making that smooth enough that you don’t feel it was one of the biggest challenges.”
TopSpeed’s Take
The CLA doesn’t make anywhere near the power the Porsche Taycan does, but Mercedes was able to justify the extra cost given the benefits. It’s expected the model will be considerably cheaper than Porsche’s EV as well, meaning this transmission type could be viable lower down in the market. If that is indeed the case, and other OEMs begin to see benefits from using these two-speed units, expect to see more of them enter the market in the coming decades.
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