FCA What's Behind - episode 5: four-wheel drive
- The fifth installment in our series explores the four-wheel drive: a fundamental technology for off-road thrills, but also for track driving and daily use.
- The video material features overviews of remote places where cars are tested on different surfaces and in extreme weather conditions, so that their off-road systems face really tough tests.
- The mission of the Jeep brand - off-road pioneer and inventor of the SUV concept - is clear from its claim "Go Anywhere, Do Anything": a goal pursued using extremely advanced mechanical solutions.
- That is why only Jeep SUVs can flaunt the Trail Rated badge: they have passed tests on traction, water fording, maneuverability, articulation and ground clearance.
- The Fiat brand boasts an important 4x4 tradition too: in 1983 its Panda was the first ultra-compact 4-wheel drive transverse-engine car.
- Alfa Romeo has a special approach to four-wheel drive: the exclusive Q4 system offers the sheer driving pleasure of rear-wheel drive but with 4x4 safety and control.
- All these brands are rearing to develop this traction technology to tackle future challenges: the new plug-in hybrid SUVs Jeep Renegade and Compass will adopt a dedicated electric motor for an even more powerful rear axle system.
The new FCA What's Behind installment visits the most inaccessible places on earth, doing so in total safety in very different kinds of car that all share 4X4 technology.
The four-wheel drive is one of FCA's proudest traditions: in different technical versions it performs in various brand models. It is only natural to firstly mention the brand that pioneered this system: Jeep®. The first Jeep was built in 1941, designed to operate in various places on various missions: hence its iconic claim, "Go Anywhere, Do Anything". The first 4x4 car in history was called Willys and it was the first ever mass-produced off-road vehicle. In 1949, Jeep invented the first Sport Utility Vehicle, the Willys Wagon. The SUV then turned luxury in 1963 with the Wagoneer, the first to use automatic transmission and independent front wheel suspension.
Jeep®: history and future
The Jeep brand's proverbial offroad performance has evolved by anticipating market trends and taking advantage of developments affecting the automotive world in a broader sense. Recently, the development of extremely advanced mechanical solutions has gone hand-in-hand with on-board electronics and new standards of handling and on-the-road driving comfort. Today, four-wheel drive is integrated with latest-generation safety and driver assist systems, and in the very near future we will see the electrification of Jeep Compass and Jeep Renegade: an epochal milestone for 4x4 vehicles. The plug-in hybrid SUVs will improve Jeep's legendary off-road performance. How? Because rear axle traction will no longer be provided by a drive shaft, but by a dedicated electric motor: this allows the two axles to be uncoupled and the drive torque to be managed independently. The new system is more powerful than an all-mechanical one, thanks to the high torque of the electric unit and the possibility of distributing it with the utmost precision when accelerating or driving off-road.
The importance of worldwide testing
In previous FCA What's Behind episodes, we have shown the vital importance of tests and trials, carried out on the most difficult surfaces in the world and in the most extreme climatic conditions. On snow and ice - as seen in Arjeplog, Sweden, or in icy northern Michigan - transmission systems and the precision of torque distribution, essential for driving on low grip surfaces, are tested to their limits. On the borders of deserts - as in Upington, South Africa - the resistance of components and materials are examined, and the vehicle's ability to deal with differing but always scorching sand and desert rock surfaces. Jeep research and development areas play a decisive role, whether in the Balocco Proving Ground in Piedmont or among the giant boulders of the Rubicon Trail... the world's toughest off-road testing ground, where Jeep SUVs earn their Trail-Rated badges.
From one side of the ocean to the other: Fiat makes a pocket 4x4
Jeep is not the only FCA brand with an impressive 4x4 tradition: in 1983 Fiat created the smallest 4x4, making the four-wheel drive truly democratic. That was the Panda, the first ultra-compact, transverse-engine car to adopt a full-traction system. A manually selectable four-wheel drive, a 965 cm3 46 HP engine, a reinforced body and an ultra-low first gear: an authentic, unstoppable, small off-road vehicle. Over time the models, the fittings and the technologies have changed, but the Panda remains the best selling 4x4 city car, also offering daily escapes from urban routine.
Not only off-road vehicles: 4x4 and driving thrills with Alfa Romeo
But the advantages of four-wheel drive are not only savored in off-road conditions: it optimizes on-road performance, in all weather and road surface conditions. The development process for this type of performance is very different: an area where Alfa Romeo provides the ultimate example.
Giulia and Stelvio employ refined systems, offsprings of a top-down approach, achieved by adopting technology designed for the Quadrifoglio, a towering peak of Alfa Romeo design.
Traction plays a hugely important role in Alfa Romeo's unparalleled driving pleasures: the Q4 technology is designed to manage the vehicle's thrust in a reactive and predictive manner, thus guaranteeing the highest levels of performance, efficiency and safety.
The heart of the Q4 is its active torque distribution system (active gearbox or ATC). This monitors grip conditions and driver input in real time, always guaranteeing optimal performance. Alfa Romeo's exclusive Q4 system enables rear-wheel driving up to the point when - as the grip limit approaches or at the driver's request - it can close the clutches present in the distribution system and transfer up to 50% of the torque to the front axle in just 150 milliseconds.