Stellantis patents three-speed gearbox for electric cars in the USA
Stellantis’ patent was filed with the United States Patent and Trademark Office (USPTO), filed on October 25, 2023, and granted on May 1, 2025. It outlines a powerful and compact solution aimed at delivering both off-road power and highway efficiency. These two performance goals are often at odds in today’s more prevalent single-speed electric vehicle designs.
The newly patented gearbox introduces a multi-speed solution using two planetary gearsets and four clutches, which include two brake-type and two friction-type, to create three distinct gear ratios within a single electric drive unit.
The first gear ratio uses the third clutch to tie the motor directly to the sun gear of the first planetary gearset, while the first clutch locks the carrier to the housing. This slows output speed and boosts torque—ideal for towing, crawling over rocks, deep snow, or sand.
Stellantis writes that the second ratio works by “locking the sun gear to the housing (via the second clutch) and sending torque through the carrier using the fourth clutch. This gives a higher gear ratio more suitable for normal driving conditions,” as Stellantis wrote.
Finally, in the third gear, “the sun gear and carrier are locked directly to the electric motor’s output shaft using the third and fourth clutches. This effectively bypasses the reduction, giving a 1:1 ratio for maximum efficiency at highway speeds.”
No vehicle has been announced yet which will use the new system, but moparinsiders speculates that “Ram’s upcoming electric trucks, Jeep’s electrified off-roaders, and Dodge’s new-generation muscle cars” are all reasonable guesses.
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