Stellantis explores 2-speed transmission for off-road EVs

Stellantis is designing a two-speed transmission for use in electric off-roaders, a newly surfaced patent filing shows.

Most EVs (the Porsche Taycan being a notable exception) use single-speed transmissions, as the instantly available torque of electric motors makes multiple gear ratios unnecessary. But in a patent application published by the United States Patent and Trademark Office (USPTO) on Jan. 23 (and originally filed on April 28, 2023), Stellantis argues that this may not be ideal for off-road vehicles.

The automaker notes that while off-roading generally requires a lot of torque at low speeds, the gearing that makes this possible isn’t ideal for on-road efficiency and range. So Stellantis proposes including one gear for on-road driving and one for off-roading.

The transmission itself would use two planetary gear sets in a housing mounted between an electric motor and an axle’s half shafts, with clutches controlling torque output. These clutches would both engage one of the two gears and control output to the wheels.

The clutches could also be used to rotate the half shafts in different directions, allowing an EV “to rotate about a pivot point to allow improved mobility on low friction,” the application states. That sounds a bit like Rivian’s shelved Tank Turn feature, or the upcoming electric Mercedes-Benz G-Class’  G-Turn feature. Stellantis also mentions using this hardware “to achieve high-speed off-road maneuverability.”

A patent application does not serve as confirmation of production plans, but Stellantis has been experimenting with electric off-roaders with the Jeep Magneto concepts. That’s likely in preparation for the next-generation Jeep Wrangler, which according to a union document will be sold exclusively as either an EV or series plug-in hybrid.