Jeep Wrangler Adds Plug-In Hybrid, 25 Mile Electric Range

When the latest generation Jeep Wrangler debuted in late 2017, it offered the first 48V mild hybrid system in the US market on its new 2.0-liter turbocharged four-cylinder. Fiat Chrysler promised that was just the beginning of its Jeep electrification plans with a plug-in hybrid variant coming in 2020. Jeep first publicly showed the new Wrangler 4XE (pronounced four-by-E) at CES last January, but aside from the charging port on the left front fender, no other details were offered. With the Wrangler 4XE due to start production in December, we now have those details and this looks to be quite an impressive beast. 

Unlike the first plug-in hybrid drive unit developed by FCA for the Pacifica minivan, the Wrangler is using the new ZF PHEV 8-speed automatic. Like most rear and four-wheel-drive hybrid vehicles, this transmission is a modular design that replaces the traditional torque convertor with an electric motor and a clutch to decouple the engine. A second variable clutch between the motor and transmission input helps to ensure smooth engagements. According to ZF, this unit is only 30 mm longer than the conventional version used for internal combustion applications. 

In the Wrangler, Jeep is pairing this transmission with the same 2.0-liter turbo four which also retains its 48V belted starter generator system. When used on its own, the four-cylinder produces 270-hp and 295 lb-ft of torque. In combination with the 90-kW, 250 n-m electric motor, the total system output of the Wrangler 4XE is quoted as 375-hp and 470 lb-ft of torque, nearly the same power and 60 lb-ft more than the 5.7-liter Hemi V8 in the Ram 1500 pickup. 

According to Micky Bly, FCA’s head of global propulsion systems, that’s enough to push the Wrangler 4XE to 60 mph in just six seconds despite the extra 500-lbs it carries compared to a standard V6 Wrangler. But while a performance boost is always nice, it’s not the primary reason for adding a plug-in hybrid powertrain to the Wrangler. 

The 17-kWh lithium ion battery pack contains 96 prismatic can cells produced by Samsung SDI. Like most current automotive applications, Samsung is using a nickel manganese cobalt chemistry for the Wrangler cells. The pack itself accounts for much of the extra mass and it is packaged underneath the rear seat which now has flip and fold capability to access the pack for service. 

An integrated dual charging module combines the AC charger with a DC-DC convertor that provides 12V power to traditional vehicle systems. This module also incorporates the inverter that switches between the AC power used by the motor and DC stored in the battery. The pack is liquid cooled and sealed in order to maintain the 30-inch water fording capability, because this is afterall a Jeep first and foremost. Jeep claims no loss in passenger or cargo capability with the PHEV and approach, departure and breakover angles also retained. However, the packaging constraints of the battery mean that the plug-in is only available with the four-door Wrangler. 

The 4XE uses the same automatic transfer case as internal combustion Wranglers and is expected to have the same crawl ratio of up to 80:1 through the Dana 44 axles on the Rubicon. 

Bly estimates that the Wrangler 4XE will provide 25 miles of all-electric driving range and average 50 MPGe in typical driving. While that won’t challenge the roughly 40 miles available from the Ford Escape and Toyota Rav4 PHEVs, the Wrangler is larger and a lot less aerodynamic. It can also go places those crossovers can’t even dream of traversing. 

The Wrangler will offer a three driver selectable modes for the drive system:

• Hybrid, which lets the computer blend the engine and electric drive for optimum efficiency
• Electric, which lets the driver determine when to run with the engine off as long as the battery has sufficient charge
• eSave, which preserves battery charge and runs mainly off the engine. In eSave mode, the driver can also choose whether to just maintain the battery at whatever state of charge it has or drive the engine and motor as a generator to replenish the battery so it can be used later. 

As in all electrified vehicles, there is also regenerative braking. The standard regen mode will provide up to 0.25g of deceleration when the driver applies the brakes, enough for most braking situations without adding in the friction brakes. A Max Regen mode is also available that provides more aggressive braking when the accelerator is released. This mode provides more replenishment of the battery for more electric range but could also prove very useful when navigating off-road trails by enabling single pedal driving. 

Like other plug-in vehicles, it will come with a charging cord that owners can use to replenish the battery overnight from a standard 120V outlet. With a 240V level 2 charger, the battery can be topped up from empty in about two hours. 

Over the next few years, Jeep plans to offer electrified powertrain options on every Jeep nameplate. PHEV versions of the Compass and Renegade already went on sale in Europe this summer and FCA previously announced plans to offer battery electric Jeeps in China. So far there is no word on when or if those variants will be offered in North America. What we will definitely be getting is PHEV variants of the new Wagoneer and the next-generation Grand Cherokee. 

Production of the Wrangler 4XE kicks off in Toledo in December and vehicles should be arriving at Jeep dealers early in the new year. No pricing is available yet but this powertrain will be offered with a base 4XE, Sahara and Rubicon trims.