Isbark.com

While Jeep owners and electrification aren’t always on the same page, that hasn’t stopped Jeep from trying to merge the two. It might even make Jeep try harder. Just look at the Wrangler 4xe, the best-selling plug-in in the US since it was introduced several years ago.

The most clever bit about 4xe system is that it offers a low-range transfer case along with electric power. So you can still crawl over boulders and out of tight spots without using gasoline. But what about for fully electric models like the new Jeep Recon? A new patent from Jeep’s parent company, Stellantis, promises to bring the ultimate in off-road gear reduction to electrics, promising to make them even better.

Three-Speed Transmission Delivers Real Low-Range Gearing

First spotted by Mopar Insiders, Jeep’s patent is for a three-speed gearbox attached to an electric drive module. Much like a conventional automatic, it uses planetary gearsets and four clutch packs to alter the torque and speed output from the electric motor.

In technical terms, the first planetary gearset connects to the motor output with a clutch. The second planetary gearset is connected to the first one with another clutch. It can apply output to the various sun and ring gears to create three different end ratios. In the idea, the clutches can be one of a variety of types, including one-way selectable clutches, and it can all be attached to a locking differential, and can drive two or four wheels, allowing for a single motor to deliver 4×4 drive.

Gearboxes in EVs aren’t unusual. Porsche, for one, uses a two-speed unit on the rear axle in two-motor Taycan models. But while that gearbox is used to raise the top speed of the car, Jeep is planning something different.

As pointed out in the patent, typical single-speed EVs deliver excellent torque at pavement driving speeds, but they can’t deliver sustained high torque for off-pavement driving. If they can deliver high torque, they can’t deliver range and performance requirements on-road. The idea behind this is to fix that.

Two And Four-Wheel Drive Low Ranges Available

Jeep’s first gear will be 2-Lo or 4-Lo (because the new drive module and twin-motor systems allow both, so why not?) and be “capable of meeting high-torque requirements such as those associated with heavy towing, trail terrain, vehicle recovery, and stump removal.” So it’s meant for doing low-speed, high-torque EV things.

The company didn’t mention a ratio, but let’s look at other Stellantis products for an idea of what this thing could do. Jeep doesn’t have a 4×4 EV right now, but Dodge does in the form of the Charger. The Charger R/T delivers 404 lb-ft of torque split between its two motors.

How much torque does that turn into with 4Lo gearing? We’ll assume Jeep gives this the same 4.0 low-range ratio as the current Wrangler Rubicon. So 404 times the 11:1 differential gearing and the 4.0:1 Lo range, and suddenly you have 17,776 pound-feet of torque. That’s not far off from the 22,786 lb-ft the current 2.0-liter Wrangler Rubicon makes using the same math. And that’s making assumptions about the torque being the same as the Charger Daytona, and the ratio being the same as the Rubicon. The reality is that Jeep can tailor the ratio to get as much, or little, wheel torque as it wants.

Related

Future Cars: Why The 2026 Jeep Cherokee Is Such A Big Deal

A new Cherokee is on the horizon, but will it make up for past failures?

Better yet, an electric motor will make all that torque from 0 rpm. The gas engine needs to rev to 3,000 rpm to make its max. Plus, Jeep could use different ratios because it isn’t limited by the space inside the transfer case, like it is with current gas model designs.

It was close to two years from the time Stellantis applied for this patent until the time it was issued. But if you’re going to get your electric Jeep (or potentially Ram REV truck as well) stuck, it will be time very well spent.

Source: USPTO (via MoparInsiders)