Explained: The Jeep Grand Cherokee 4xe drivetrain

Jeep has confirmed it will bring the plug-in petrol-electric Jeep Grand Cherokee 4xe to Australia in the second-half of 2022.

It is the first electrified Grand Cherokee and the first electrifed Jeep to come to Australia.

The Grand Cherokee’s PHEV system combined a direct injection 2.0-litre turbo-petrol four-cylinder engine and eight-speed auto with two electric motors and a 17kWh 400-volt battery.

Jeep claims the Grand Cherokee has a usable electric-only range of about 40km.

READ MORE: First Jeep EV confirmed for 2023
READ MORE: Jeep Wagoneer makes high-tech comeback as PHEV hybrid
FEATURE: Why electric cars and 4WDs will be more capable off-road
READ MORE: Jeep teases electric future with Wrangler-based Magneto concept

The 4xe drivetrain produces a combined 280kW and 637Nm and claims a combined fuel consumption number of just 4.1L/100km. There’s so far no breakdown of the maximum outputs of the petrol engine and electric motors.

However, in EV mode there is the potential for better off-road performance given the torque delivery of an electric motor. Jeep is one manufacturer that has said EVs will be better than ICE 4WDs off-road.

How does Jeep’s 4xe PHEV work?

The 2.0-litre turbocharged inline four-cylinder engine is shared with others within the Stellantis family (which includes brands such as Peugeot, Citroen, Chrysler, Opel and Maserati). A twin-scroll turbocharger is mounted to the cylinder head to reduce lag (the time it takes for the turbo to spin up to its operating speed). Electric power steering and an electrically driven air-conditioning system reduce how much power is drawn from the engine.

While there are two electric motors, only one of them drives the wheels.

The second one effectively replaces the alternator. It provides the kick to restart the engine as part of the start-stop operation and also generates electricity for the battery pack.

A larger high-voltage electric motor is mounted in the transmission, replacing the torque converter. Because it’s driving through the transmission it can send e-drive to all four wheels.

The Jeep Grand Cherokee 4xe’s battery units and controls mount underneath the vehicle, packaged under the floor and protected by a series of skid plates to protect from damage when off-roading.

The battery pack system includes a heating and cooling circuit to keep the battery at its optimum temperature. The system includes a heater unit and chiller that uses the Grand Cherokee’s air-conditioning to reduce coolant temperature when needed.

The electronics as part of the hybrid system have been sealed to allow the Jeep Grand Cherokee 4xe to ford up to 610mm of water.

The charge port is beneath a push-open/push-close cover near the left front wheel. An LED battery level monitor sits on top of the instrument panel, making it easy to check battery state of charge during charging.

4xe E Selec drive modes

E Selec allows the Jeep Grand Cherokee 4xe driver to tailor the hybrid powertrain to different conditions, depending on whther the driver wants maximum performance, efficiency or a blend.

The driver selects the drivetrain mode via buttons on the instrument panel. Those drive modes are:

Hybrid: Provides what the onboard computer determines is the best blend of torque from the electric motor and ICE. It’s all about providing an easy-to drive combo that provides fuel efficiency without compromising on performance.

Electric: As the name suggests, it allows the 4xe to drive only using the main electric motor and battery. Obviously it depends on the available charge in the battery and how much performance the driver is calling on through the throttle pedal. In EV mode the 4xe produces less power (Jeep hasn’t detailed the EV-only outputs), but if you press the throttle hard enough it will automatically call on the petrol engine as well to tap into the full 280kW and 637Nm.

eSave: The idea is to maintain the current level of charge by having the petrol engine doing most of the work. You’ll use more fuel, but that electricity in the battery will be there for use later.

Regardless of the mode selected, the Grand Cherokee 4xe operates as a hybrid once the battery nears its minimum state of charge.

The instrument cluster and central touchscreen also has Eco Coaching Pages, which display real time energy flow and monitor things such as regenerative braking.

Regenerative braking can provide up to 0.25g of deceleration, in turn feeding electricity back into the batteries.

There’s also a Max Regen mode for more aggressive deceleration.