2021 JEEP WRANGLER 4XE
Jeep’s new plug-in-hybrid Wrangler promises 375 horsepower and 49 MPGE but struggles to smoothly blend its gas and electric power. Complicates a Simple Machine
Depending on how you frame it, the Jeep Wrangler 4xe is either a relic of the past or one of the most technologically complex vehicles on the road. Body-on-frame construction, solid front and rear axles, and a fabric roof make the Wrangler a sort of 21stcentury self-propelled covered wagon. Yet the 4xe plug-in hybrid follows the lead of sciencefair projects such as the Chevrolet Volt and the Toyota Prius Prime, running on gas, electricity, or a combination of both in the interest of greater efficiency.
The 4xe (pronounced “four by E”) sandwiches a 270-hp turbocharged inline-four between a 44-hp motor connected through the accessory belt at the front and a 134-hp motor taking the place of the transmission’s torque converter at the back. The motors draw power from a roughly 14.0-kwh lithium-ion battery stashed under the rear seats. Whether the 4xe is running in Electric mode or as a hybrid, torque is routed to the wheels through an eight-speed automatic transmission and a transfer case that offers rear-wheel drive, all-wheel drive (4WD Auto), and high- or low-range four-wheel drive for the off-road crowd.
HIGHS: Guilt-free electric motoring, goanywhere capability, one vehicle that does the job of many.
In other words, the power flow through the Wrangler 4xe’s running gear is, at times, harder to follow than the plot of Inception. At least the net results are easy to understand: 375 horsepower, an EPA fuel economy of 49 MPGE with the battery charged, and 21 miles of guiltfree electric driving before the gas engine kicks on. The 4xe promises to combine contradictory attributes—power and efficiency—into a single product that would have been unthinkable just 10 years ago, like those business-casual sweatpants you can now wear to work. The plugin hybrid makes the same torque—470 lb-ft—as the V-8-powered Wrangler Rubicon 392, which is rated at just 14 mpg combined.
In Car and Driver testing, a $62,415 Wrangler Unlimited Rubicon 4xe hit 60 mph in 5.5 seconds, which makes it quicker than anything with recirculating-ball steering needs to be. (The Rubicon 392, a vehicle designed around absurd excess, should be about a second quicker, but we haven’t tested one yet.) You’ll have to shift into 4WD Auto if you want to hustle the plug-in hybrid that hard, because in two-wheel-drive mode the Wrangler throttles the torque, resulting in a 60-mph time that’s 1.3 seconds slower. LOWS: Sluggish in Electric mode, clunky in Hybrid mode, unexceptional fuel economy once the battery is depleted.
When the gas and electric powertrains are working in harmony, this Wrangler drives well enough, but transitions between pure electric driving and hybrid operation are can be slow and jarring. If the battery is depleted or the driver asks for more power than the electric motor can deliver, the inline-four often jumps into action with all the grace of a middle schooler at their first dance. There are pregnant pauses long enough that you might ask out loud “What the hell is happening?” before the Jeep starts accelerating with any urgency. Other times the engine makes a rushed, jerky entrance. Driving the Wrangler 4xe in suburban traffic is a constant reminder that calibrating two powertrains to behave as one is more than twice as complicated as tuning a single propulsion source.
An Electric mode remaps the accelerator so that the gas engine kicks on only if you flatten the right pedal. Annoyingly, if you always want to start out driving electrically, you’ll have to switch into this mode every time you start the 4xe. But you probably won’t, because driving that way, you’re moving a 5318-pound brick with just 134 horsepower. That’s enough to keep up with traffic, but treating the 4xe as an EV doesn’t have the same fun, torque-rich punch we’ve come to associate with electric driving.
To get the full fuel-economy benefit, you’ll have to stay close to home and plug in often. A 150mile trip with only a single charge tanked our average fuel economy over roughly 200 miles to a dismal 16 MPGE. Owners who are religious about plugging in and puttering around in Electric mode will certainly fare better, although we suspect most buyers will come up well short of 49 MPGE. Once the battery has been depleted, the 4xe actually gets worse fuel economy than a Wrangler powered by the turbo four with none of the plug-in-hybrid hardware (20 versus 22 mpg combined). Blame the extra 800 pounds that the 4xe carries wherever it goes.