More “green”, but no less capable
The new Jeep Wrangler Unlimited 2.0 Turbo 4xe is the plug-in hybrid version (that is, rechargeable from a socket) of a reference model for enthusiasts: a car that has made, and continues to make, off-road history. An increasingly widespread solution, electrification makes it possible to limit CO2 emissions and now it also arrives in a “hard and pure” off-road vehicle, the “real” ones, with a very sturdy frame with side members, reduced gears and lockable differentials. We must immediately point out to the skeptics that, despite the addition of electric motors and batteries (which bring the weight of the car from just over 2 tons to over 2300 kg), the Jeep Wrangler Unlimited 4xe it does not lose an iota of its off-road driving skills, thanks to the brand new plug-in hybrid system which is designed to make it even more effective on difficult terrain. Starting from the power, which rises from the 272 hp of the 2.0 turbo petrol engine to 380 hp combined and, above all, thanks to the engine torque of 637 Nm: a boon, when you have to overcome big obstacles and you need all the inspiration possible. The same aesthetically and in the passenger compartment as the other Wrangler Unlimited (ie the long wheelbase versions with four side doors, while for the “short” ones the plug-in hybrid is not foreseen for now), the 4xe is spacious, well finished, with soft plastics and robust appearance. We would have preferred, however, a greater number of storage compartments, while the luggage compartment capacity of 533/1910 liters is not bad.
Basically, the four-cylinder remains
The hybrid system of the Jeep Wrangler Unlimited 2.0 Turbo 4xe it consists of three engines. First of all, there is the 2.0 petrol direct injection, equipped with a low inertia turbocharger mounted directly on the cylinder head and with a specific cooling circuit for the turbo, the intake system and the throttle body. The thermal unit is combined with a water-cooled high-voltage motogenerator placed on the front of the engine, replacing the traditional alternator. Connected via a belt to the crankshaft pulley, it delivers additional power, manages the operation of the Stop & Start system and, when released, generates electricity to be sent to the accumulators. The Wrangler 4xe does not feature a conventional 12 volt starter motor, but is equipped with a 12 volt battery to power accessories.
The second motor generator is housed in the front of the gearbox, and replaces the traditional torque converter of the automatic transmission. Two clutches make the different operating modes possible. The first is placed between the electric motor generator and the 2.0; when it is open, the Jeep Wrangler 4xe it only travels on current, while once closed both motors provide drive torque. The second clutch is mounted behind the electric motor and manages the intervention of the transmission. This architecture makes it possible to exploit the advantages of the hybrid system, while maintaining the off-road capabilities and characteristics that have always distinguished this model. The combustion engine and the two motogenerators are installed upstream of the Wrangler’s 4×4 mechanical system, therefore they allow the simple and intuitive four-wheel drive system to remain unchanged, but improved in performance, with official acceleration from 0 to 100 km / h. in just 6.5 seconds against the 7.6 of the Wrangler with only the 2.0 turbo of 272 HP.
Guadi no problem
The Jeep Wrangler 4xe has a 96-cell, 17.3 kWh, 400-volt lithium-ion battery. It is located under the sofa and receives power through a socket in the left front fender (the house talks about less than three hours for a complete regeneration, provided you have a charger of at least 7.4 kW). Dedicated heating and cooling circuits allow to keep the “stack” at optimal temperatures, so as not to worsen its performance even in very severe conditions of use. All high voltage electronic components and systems, including the wiring between the battery and the electric motors, are sealed and waterproofed with particular care, so much so that, like all Jeep Wrangler Rubicon, the 4xe also boasts a wading capacity of up to 76 cm. and a minimum height from the ground of 25.3 cm.
Few limits, even in electric
The Rock-Trac drive system from Jeep Wrangler 4xe Rubicon, the most complete, includes electric locks for the front and rear differentials and an electrically disconnected front stabilizer bar (used to increase suspension travel and better tackle the most difficult obstacles). Four driving modes: 2H (from High, to indicate normal gears, and with only two driving wheels); 4H AUTO (with the four-wheel drive that are inserted in case of need); 4H Part-Time (permanent all-wheel drive, for surfaces with very low grip) and 4L (with, in addition, reduced gears). Noteworthy are the characteristic angles of the Rubicon 4xe: the angle of attack is equal to 36.6 degrees, that of the back is 21.4 degrees and the exit angle is 31.8 degrees. The integration of the electric power supply in the 4×4 traction system ensures immediate availability of the drive torque: the car has a prompt response and, without putting the 2.0 under stress, you can proceed on the most inaccessible terrains with extreme ease and almost in silence ( only the slight hiss of the electric motor is heard). In our test we went up in the woods, along high mountain paths, with extreme ease. Being able to enjoy the pleasant “noise” of nature, without any contamination of the heat engine (which, among other things, under stress, with the reduced, tends to raise the number of revolutions a lot).
He prefers dust to asphalt
Comfortable, but a little noisy (aerodynamically and tire rolling) and unwieldy on asphalt (where, starting with the battery charged to 90%, we traveled 180 km with an average consumption of 12.5 km / l, according to the on-board computer), the Jeep Wrangler Unlimited 4xe it allows you to travel about fifty kilometers with zero emissions, before the 2.0 starts operating, in hybrid mode. In addition to the “battery” and hybrid operation (with gasoline and electric engines working together managed by the control unit), the car has another driving mode, the E-Save, which gives priority to the four cylinders in order to maintain unchanged (or even increase) the battery charge for subsequent uses, such as driving with zero emissions on off-road tracks or in urban areas. In our test on the highway we used the mode that allows you to recharge the battery through the operation of the internal combustion engine: in E-Save the consumption of gasoline increases a lot, so it is better not to “abuse it”, but in doing so we were able to bring the “pile” from 39% to 80% in a 90 km journey, at the end of which the off-road route awaited us.
Rich, but expensive
The Jeep Wrangler Unlimited 2.0 Turbo 4xe in the Rubicon set-up it is well made, technological and well equipped: as standard it has two-zone “climate”, adaptive cruise control, front and rear parking sensors with rear view camera, full LED headlights, navigator and hi-fi 552W with nine speakers. However, the 71,050 euros of the price list are not few, and do not include important electronic driving aids, such as automatic emergency braking, in the Safety package at 1,200 euros. The Sahara, less devoted to “hard” off-roading (it does not have the front stabilizer bar disconnection and differential lock), saves 1,500 euros.
In our opinion
> Off-road driving. By engaging the electric 4×4 drive, with reduced gears, locking the differentials and disconnecting the front stabilizer bar, the car climbs everywhere, almost silently.
> Finishes. The materials of the dashboard, with soft upholstery, metal details and pleasing plastics, are more of a luxury sedan than an off-road vehicle.
> Hybrid system. It is powerful, smooth and well matched to the 8-speed automatic transmission.
> Rustles. The squared shape of the body does not help aerodynamics; the noise is evident.
> Price. Okay, the car is a concentrate of technology, but the price list is really expensive and not everything is standard.
> Storage compartments. A bit spartan in this respect, the car only has nets in the doors and few compartments; small drawer in front of the front passenger.