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BREAKDOWN: 2021 Jeep® Wrangler Rubicon 4xe VS Rubicon 392:

Which Do You Choose? Electric Or HEMI?

The Jeep® brand has released two new versions of its iconic off-roader going into the 2021 model year. The two variants, couldn’t be at the opposite ends of the spectrum. One is environmental friendly with a gas/electric powertrain, while the other is a HEMI V8 performance monster. So we thought we would compare to two different models coming off the Toledo Assembly Complex line this coming year.

2021 Jeep® Wrangler Rubicon 4xe. (Jeep).

When it comes to powertrain, there isn’t couldn’t be two more different layouts. The 2021 Jeep Wrangler Rubicon 4xe powertrain integrates two electric motors and a 400-volt battery pack with the popular 2.0-liter turbocharged inline-four-cylinder engine along with the ZF-sourced 8-speed automatic transmission making a combined 375 horsepower (280 kW), 470 lb.-ft. (637 N•m) of torque and producing an estimated 50 MPGe. The 2021 Jeep Wrangler Rubicon 392’s 6.4-liter (392 cubic-inch) HEMI V8 is rated at 470 horsepower (354 kW) and 470 lb.-ft (637 N•m). of torque. This means both models ultimately make that same output when it comes to torque.

2021 Jeep® Wrangler Rubicon 392. (Jeep).
Powertrain 2021 Jeep® Wrangler Rubicon 4xe 2021 Jeep® Wrangler Rubicon 392
Engine 2.0-liter Turbocharged I-4 6.4-liter HEMI V8 
Horsepower/Torque 270 hp (200 kW)/295 lb.-ft. (400 N•m) 470 hp (354 kW)/470 lb.-ft. (637 N•m) 
Compression Ratio 10.0:1 10.9:1
Fuel Requirement Minimum unleaded regular, 87 octane (R + M)/2; 91 octane or higher recommended
for optimum fuel economy and performance
Premium 91 octane (R+M)/2 — required
Fuel Tank Capacity (gallons) 17.2 21.5
eTorque Belt-Start Generator Motor 44 hp (33 kW)/39 lb.-ft. (53 N•m) N/A
Integrated Transmission Traction Motor 134 hp (100 kW)/181 lb.-ft. (245 N•m) N/A
Total Powertrain Output 375 hp (280 kW)/470 lb.-ft. (637 N•m)  470 hp (354 kW)/470 lb.-ft. (637 N•m) 
Max. Gross Trailer Weight 3,500 lbs. 3,500 lbs.

When you compare the 2021 Jeep Wrangler Rubicon 4xe and the 2021 Jeep Wrangler Rubicon 392, on paper, there are just as many similarities as there are differences. Both models utilize ZF-sourced 8-speed automatic transmissions, however, the two units are quite different.

2021 Jeep® Wrangler Rubicon 4xe Powertrain Components. (Jeep).

Rubicon 4xe models take advantage of the new 8P75PH 8-speed automatic transmission. The 8P75PH uses a high-voltage motor-generator is mounted at the front of the transmission case, replacing the conventional torque converter of an automatic transmission. Two clutches work to manage power and torque from the e-motor and engine. A binary clutch (on/off) is mounted between the engine and the motor. When this clutch is open there is no mechanical linkage between the engine and the e-motor, which enables it to propel the Rubicon 4xe in electric-only mode.

2021 Jeep® Wrangler Unlimited Rubicon 392 Powertrain Components. (Jeep).

The Rubicon 392 uses the 8HP75 automatic, which allows for steering-wheel-mounted paddle shifters as standard equipment. The 8HP75 delivers crisp shifts and performance tuning helping to maximize acceleration at launch.

Transmission 2021 Jeep® Wrangler Rubicon 4xe 2021 Jeep® Wrangler Rubicon 392
  8P75PH PHEV 8-Speed Automatic 8HP75 8-Speed Automatic
Description Plug-in hybrid automatic transmission with AC traction motor with Motor Interrupting
Clutch and Integrated Launch Element; adaptive electronic control and Auto Stick
driver-interactive manual control
Adaptive electronic control or Electronic Range Select (ERS) driver-interactive
manual control and electronically modulated torque converter clutch
Gear Ratios    
1st 4.71 4.71
2nd 3.14 3.13
3rd 2.11 2.10
4th 1.67 1.67
5th 1.28 1.28
6th 1.00 1.00
7th 0.84 0.84
8th 0.67 0.67
Reverse 3.32 3.30
2021 Jeep® Wrangler Rubicon 4xe. (Jeep).

Powertrains aren’t the only thing that differs between the two models. Both utilize legendary Jeep four-wheel-drive (4×4), however, they both take different approaches. The Rubicon 4xe uses the standard Rubicon model’s optional full-time Rock-Trac® 4×4 system that includes a two-speed transfer case with a 4:1 low-range gear ratio. On the other side of the puzzle, the Rubicon 392, ditches the Rubicon’s Rock-Trac system for the optional Selec-Trac full-time two-speed transfer case with a 2.72 low-range gear ratio, found on the popular Sport and Sahara models as its standard option.

2021 Jeep® Wrangler Unlimited Rubicon 392. (Jeep).
Transfer Case 2021 Jeep® Wrangler Rubicon 4xe 2021 Jeep® Wrangler Rubicon 392
Make MP3022OR Rock-Trac® MP3022 Selec-Trac
Type Full-Time Full-Time
Operating Modes 2WD High; 4WD Auto; 4WD High; Neutral; 4WD Low 4WD Auto; 4WD High; Neutral; 4WD Low
Low Range Ratio 4.0:1 2.72:1
2021 Jeep® Wrangler Rubicon 4xe. (Jeep).

When it comes to suspension, the Rubicon 4xe and Rubicon 392 feature a lot of the same goodies. Wrangler Rubicon models offer improved articulation and total suspension travel with help from a front axle, electronic sway-bar disconnect. Together, these components contribute to the maximum off-road prowess Wrangler Rubicon is known for. 

2021 Jeep® Wrangler Unlimited Rubicon 392. (Jeep).

The Wrangler Rubicon 4xe features an approach angle of 44 degrees, break-over angle of 22.5 degrees, departure angle of 35.6 degrees and ground clearance of 10.8 inches, and the ability of 30 inches of water fording. Thanks to a 2-inch lift, the Rubicon 392 has 10.3 inches of ground clearance; improved suspension articulation and maneuverability with an approach, break-over, and departure angles of 44.5, 22.6, and 37.5 degrees, and the ability to traverse up to 32.5 inches of water.

Suspension 2021 Jeep® Wrangler Rubicon 4xe 2021 Jeep® Wrangler Rubicon 392
Front Solid axle, link coil, leading arms, track bar, coil springs, stabilizer bar Solid axle, link coil, leading arms, track bar, coil springs, stabilizer bar
Stabilizer Bar Electronic sway-bar disconnect system Electronic sway-bar disconnect system
Shock Type High-press gas-charged monotube shock absorbers
with MTV technology and hydraulic rebound stop
High-pressure gas-charged FOX aluminum monotube shock absorbers
with hydraulic rebound stop
Rear Solid axle, link coil, trailing arms, track bar, coil springs, stabilizer bar Solid axle, link coil, trailing arms, track bar, coil springs, stabilizer bar
Shock Type High-pressure gas-charged monotube shock absorbers with MTV
technology and hydraulic rebound stop
High-pressure gas-charged FOX aluminum monotube shock
Clearances    
Approach Angle, Degrees 43.8 44.5
Breakover Angle, Degrees 22.5 22.6
Departure Angle, Degrees 35.6 37.5
Ground Clearance, Inches 10.8 10.3
Curb Weight (lb.) 5,222 5,103
Water Fording, Inches 30 32.5

It doesn’t matter which model of Jeep Wrangler you choose, all Wranglers come with standard electric power steering. Both the Rubicon 4xe and Rubicon 392 feature similar performance when it comes to steering abilities. The pair both feature the same turning diameter of 39.4 feet and have a lock to lock to about 3.1 turns.

Steering 2021 Jeep® Wrangler Rubicon 4xe 2021 Jeep® Wrangler Rubicon 392
Type Electro-Hydraulic Power Electro-Hydraulic Power
Overall Ratio 13.7:1 14.3:1
Turning Diameter (Curb-To-Curb) (ft) 39.4 39.4
Steering Turns (Lock-To-Lock) 3.1 3.13
Power Steering Pump Electro-Hydraulic Electro-Hydraulic

When it comes to brakes, both of the models come with different setups than the standard Rubicon. Regenerative braking is a key part of the Rubicon 4xe’s eco-friendly equation. When the driver steps on the brake pedal, the powertrain control engages the maximum available regenerative braking, up to 0.25 g, from the electric motors to slow the vehicle, augmented with the Wrangler’s traditional friction brakes. The regenerative braking feature also extends the replacement period for brake pads.

2021 Jeep® Wrangler Rubicon 4xe. (Jeep).

With 4×4 engaged, all four wheels feed torque for regenerative braking, maximizing the energy recovery. Electricity due to regenerative braking is fed to the battery pack to maintain or increase the state of charge. The Wrangler 4xe also features the ability to maximize regenerative energy production via a driver-selectable Max Regen feature.

2021 Jeep® Wrangler Unlimited Rubicon 392. (Jeep).

With the Rubicon 392, the front brake setup stays the same as the standard Rubicon, however, the rear brakes have been upgraded from a 1.88 inch (48 mm) single-piston floating caliper with a 13.4 x .55 inch solid rotor to a new 2 inch (51 mm) single-piston floating calipers with 13.6 x .86 inch vented rotors setup to help with all the added power and weight.

Brakes 2021 Jeep® Wrangler Rubicon 4xe 2021 Jeep® Wrangler Rubicon 392
Type Hydro-electric anti-lock braking system with fully blended regeneration capacity Power-assisted, anti-lock brake system
Front    
Rotor Size & Type 12.9 x 1.1 (330 x 28) Vented Rotor 12.9 x 1.1 (330 x 28) Vented Rotor
Caliper Size & Type 2 (51) Twin-Piston Floating Calipers  2 (51) Twin-Piston Floating Calipers
Front    
Rotor Size & Type 13.6 x .86 (345 x 22) Vented Rotor 13.6 x .86 (345 x 22) Vented Rotor
Caliper Size & Type 2 (51) Twin-Piston Floating Calipers 2 (51) Single-Piston Floating Caliper
2021 Jeep® Wrangler Rubicon 4xe. (Jeep).

Standard on Rubicon 4xe models is a set of 17-inch cast-aluminum wheels wrapped in a set of LT285/70R17 BFGoodrich All-Terrain KO2 tires, the same setup found on the standard Rubicon. There is a set of Beadlock-capable wheels available for the Rubicon 4xe, through Mopar and can be installed by your Jeep dealer before the vehicle is delivered.

2021 Jeep® Wrangler Unlimited Rubicon 392. (Jeep).

When it comes to the HEMI-powered Rubicon 392, a set of BFGoodrich All-Terrain KO2 tires are also standard. However, they are wrapped around new Beadlock-capable cast-aluminum 17-inch wheels. For those looking for a little more traction, a set of Falken Wildpeak M/T tires.

Wheels 2021 Jeep® Wrangler Rubicon 4xe 2021 Jeep® Wrangler Rubicon 392
Type Painted pocket with Mid-Gloss paint and polished cast-aluminum Beadlock capable, high-gloss painted cast-aluminum
Size 17-inch x 7.5-inch 17-inch x 7.5-inch
Tires    
Size & Type LT285/70R17, on/off-road, black sidewall LT285/70R17C, on/off-road, black sidewall
Mfr. And Model BFGoodrich KO2 All-Terrain BFGoodrich KO2 All-Terrain
Revs per Mile (km) 637 (396) 645 (401)
Optional    
Size & Type   LT285/70R17C
Mfr. And Model   Falken Wildpeak M/T
Revs per Mile (km)   617 (383)

While both models retain the overall looks of the standard Wrangler Rubicon, there are subtle ways that the Jeep designers have done to help tell each variant apart and help them to have their own identity. While red accents adorn the standard “Trail Rated” Rubicon models, the Jeep design team have picked other colors to represent the other two models.

2021 Jeep® Wrangler Rubicon 4xe. (Jeep).

The Rubicon 4xe wears new Electric Blue colored accents on the tow hooks, the Rubicon and Jeep badges, and other prominent Easter Egg details. The Rubicon 4xe also features a new specific hood graphic that is outlined in the new Electric Blue color with the new “4xe” text that allows the body color to show through. Inside, the Electric Blue theme continues as the highlighted stitching on the seats and various trim pieces.

2021 Jeep® Wrangler Unlimited Rubicon 392. (Jeep).

For the Rubicon 392 models, Jeep designers changed the Electric Blue theme in favor of the Bronze. The Bronze theme also is found on the tow hooks, Rubicon, and Jeep badges, but can also be found on the FOX Shocks. Inside, the leather-appointed interior includes unique bronze stitching and the bolstered front seats are embroidered with Rubicon 392 script.

Another thing the two have in common is the fact that Jeep has yet to reveal any pricing details for either model. We expect to see pricing closer to the launch of each of the vehicles. We would be hard-pressed not to say that 2021 offers more choices to Wrangler fans than ever before.

Robert S. Miller

Robert S. Miller is a diehard Mopar enthusiast who lives and breathes all that is Mopar. The Michigander is not only a Co-Editor for MoparInsiders.com, 5thGenRams.com, and HDRams.com but an automotive photographer. He is an avid fan of offshore powerboat racing, which he travels the country to take part in.

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