THE Renegade has proved amazingly popular as an urban crossover meeting all the needs of a modern family while keeping that authentic Jeep styling.

It may be the first Jeep SUV to be built in Italy but it is unmistakeably a member of the Stars and Stripes family.

And now there is the Jeep Renegade 4xe - the most fuel-efficient Jeep SUV ever. I've never been a big fan of the Renegade's boxy looks and indifferent driving but the 4xe slowly won me over.

Visually, the only thing that sets the Renegade 4xe stands out from its petrol and diesel siblings is its striking blue Jeep, Renegade and 4xe badges, and an additional push cover on the vehicle's left side, towards the rear, which covers the charging port.

The line-up features three trim levels - Longitude, Limited and the ultra-rugged Trailhawk - all featuring four-wheel-drive (eAWD) and a new six-speed automatic transmission.

Each pairs a 1.3-litre turbo petrol engine with an electric motor, located between the rear axle, which is powered by an 11.4 kWh battery that can be recharged while driving or through an external charge point.

The 1.3-litre turbo engine delivers a power output of 130hp or 180hp, plus the 60hp produced by the electric motor, giving a total of 190hp in the Longitude and Limited version or 240hp in the Trailhawk model. In terms of torque, the electric motor produces 250Nm, while the combustion engine delivers 270Nm. A hefty amount.

Jeep suggests the Renegade 4xe will return up 134mpg but that's only likely if you keep it charged and stay in town. Once the charge died, I managed 38.8mpg.

Inside the cabin, the Renegade 4xe's standard features include the company's latest Uconnect 8.4-inch full-colour touchscreen with Apple CarPlay, Android Auto and DAB radio. Ruby red accents adorn the air vents, speakers, and centre console bezels on the Trailhawk trim here.

The Renegade's high roofline and range of seat adjustments mean you'll have no trouble getting comfortable in the front seats, even if you're more than 6ft tall.

Back seat passengers will find a little less legroom but won't find it unduly uncomfortable - especially with all that headroom and the cabin's light and airy feel due to its large side windows.

There's room for 330 litres of luggage in the boot - not a huge amount - but fold the 60:40 split rear seats down and there's well over 1,200 litres of space to fill.

Jeep's legendary ruggedness has not been forgotten in the transition towards electric power. The new 4xe model retains all the off-road capabilities of the Jeep brand courtesy of its advanced 4x4 system and updated Selec-Terrain rotary control with eAWD modes and hill descent.

Traction to the rear axle is no longer provided by a prop shaft but through a dedicated electric motor allowing the two axles to be separated and the torque controlled independently in a more effective way than a mechanical system can do.

For off-road driving, customers can select Hybrid 4x4 mode and the system will automatically operate both drive systems on both axles. They can also pick 4WD Low mode to optimise response on sandy or rocky terrain or 4WD Lock to maintain permanent 4x4 traction up to 9mph and select from the five-mode Selec-Terrain traction control system.

This is a PHEV that will go virtually anywhere you want it to. And, impressively, 4x4 mode is available even when battery level is low, with Jeep's clever ‘Powerloop' function allowing the combustion engine to generate high-voltage current to power the rear electric motor.

All high-voltage electronic components are fully sealed and waterproof giving the the Renegade 4xe a wading depth of up to 40cm. The Trailhawk version is also fitted with steel skid plates for added protection when driving on rough terrain.

On the road, the Renegade 4xe doesn't quite match its off-road prowess but it feels much improved. On smooth, major roads it motors along nicely, especially with the new six-speed auto taking the strain. And Jeep has done a good job quietening down the wind and road noise created by the Renegade's boxy shape, even boxier wing mirrors and 17-inch off-road tyres.

It's still a bit wallowy if you push it through corners on twistier country roads but around town, where it can travel up to 26 miles in full electric mode, it is quiet, refined, steady, surefooted and, dare I say, fun.