4×4 for greater safety and for driving pleasure

4x4 for greater safety and for driving pleasure

All-wheel drive is very popular among Škoda drivers, and the company offers it in a number of models and versions. Take a look at how it works and what it’s good for.

21. 2. 2023 Škoda World

Škoda uses essentially two different principles for its all-wheel drive models. In cars with an internal combustion engine, the Czech carmaker traditionally uses an inter-axle multi-plate clutch to connect the rear axle. In its electric cars, the all-wheel drive is provided by a pair of electric motors. The standard rear-axle motor that powers all models in the Enyaq iV family is joined by a second motor at the front.

At present you can choose from six lines, including the fully electric Enyaq iV family, the Octavia and Superb that come in a liftback and estate version, and the Karoq and Kodiaq SUVs.

Depending on the model, Škoda now uses fifth or sixth-generation inter-axle clutches, which are characterised by low friction and high efficiency, bringing a positive effect on fuel consumption. In most cases, the all-wheel drive is connected automatically based on actual need, which is determined by a special control unit.

It works by having various sensors constantly monitoring parameters such as wheel speed, current front wheel angle, longitudinal and lateral acceleration of the car, accelerator pedal position, engine speed and torque. Based on this data, the system can detect an imminent slip of the driven axle and, in that case, instructs the inter-axle clutch to connect the second axle immediately and to the extent necessary. The connection and transmission of the calculated torque requirement takes just a few milliseconds. “The advantage of the system is not only the super-fast response, but also the possibility of torque-vectoring in the latest generation and overall high efficiency when 4×4 drive is not needed,” says Martin Hrdlička, head of chassis and powertrain development at Škoda.

martin-hrdlicka_93187704 Martin Hrdlička
head of chassis and powertrain development at Škoda

The all-wheel drive system of the Enyaq iV family of electric cars actually works very similarly, but there is no mechanical link – everything is controlled by electronics. But again, the system makes decisions based on the same data as in cars with an internal combustion engine. The rear axle is always driven by a permanent magnet synchronous electric motor. “We use an asynchronous electric motor on the front axle, which has no loss when it is not in use. This is very important in an electric car, as the motor only consumes energy when it is actually engaged in driving the car,” explains Hrdlička.

Good old 4×4s

Four-wheel drive has interested motorists and car designers since time immemorial. Due to a number of design challenges, though, the idea took a long time to be put into practice. Škoda was one of the early experimenters with four-wheel drive, with the first prototypes built as early as the 1930s. First, there were three-axle buses with two rear axles – 3 units were built. The first Škoda 4×4 vehicles appeared in the 1940s. However, it was not until recently that all-wheel drive began to become more widespread. Škoda launched the Octavia 4×4 in 1999, when all-wheel drive was not common in that price segment. Partly for that reason, the Octavia 4×4 became the best-selling all-wheel-drive car in many markets and for quite a long time before SUVs became extremely popular. The Octavia was then followed by other cars: in 2008 the Superb (then second generation) was given four-wheel drive for the first time, and in 2009 the first modern SUV from Škoda, the Yeti, arrived. More recently still, the latest models such as the Kodiaq and Karoq and the Enyaq iV family of electric cars have arrived on the scene.

The start of the 1960s saw the development of the Škoda 998, an off-road 4x4 known as the Agromobil, and the 990 shortly afterwards. Only a few prototypes were made, though, and only two survive to this day.

The challenge of developing improved safety

In most cases, all-wheel drive is engaged automatically on Škoda cars. In some situations, though, the driver can also select a specific driving mode. The Karoq, Kodiaq, Octavia Scout and Superb Scout, for example, have an Off-road mode that is ideal for driving when you’re not on the tarmac. In addition to the response of the four-wheel drive itself, the shift characteristics of the automatic gearbox change (shifting at higher revs), as does the throttle response (these are less abrupt). Even the settings of the stabilisation and assistance systems change. The Kodiaq and Karoq models have an additional Snow mode, where all-wheel drive remains engaged all the time and the gearbox shifts at a lower speed than usual. The electric cars in the Enyaq iV family have a special Traction mode for driving on non-tarmac and slippery surfaces. All-wheel drive is again active from the moment you set off, remaining engaged up to a speed of 20 km/h.

The Škoda Kodiaq RS makes easy work of icy surfaces. 

The aim of all-wheel drive is to ensure optimum traction in all circumstances, not least in winter weather when there’s snow or ice on the roads. In these situations, all-wheel drive means that each wheel of the car has to transmit less power to the road and can thus maintain traction for longer. Stable traction improves the car’s handling, which has a positive effect on the safety of passengers and other road users. As a result, the driver’s driving experience is improved even on completely dry roads. “A 4×4 provides a greater subjective sense of safety, which of course can lead to faster and riskier driving. But 4x4 is no guarantee of safety – it can’t defy physics, and drivers should remain vigilant and not overestimate either their or the car’s capabilities,” Hrdlička warns.

For the all-wheel drive system to work properly, it needs to be correctly calibrated. The primary task for the developers is to fine-tune the control electronics, but they also have to get the design and integration of the new components right. “What our adjustments focus on is the logic of the torque transfer response to the second axle. The development engineers have to think about the torque distribution for the front and rear axle when designing the software, and for cars with internal combustion engines, they have to address the rear clutch control for distributing the torque to each wheel of the axle. They also have to take into account the actual stress on the components of the entire system and their durability,” says Hrdlička, describing all the challenges faced.

A lot of choices

Škoda currently offers a wide range of all-wheel drive models, which differ in terms of type of car, bodywork and powertrain. The Octavia 4×4 has long offered four-wheel drive, as well as the larger Superb. Then there are the Karoq and Kodiaq SUVs, of course. In all these cases, customers can choose between diesel or petrol engines, with all-wheel drive available for both body versions on the Octavia and Superb. It is always paired with automatic transmission, however. All-wheel drive is also available on the Enyaq iV and Enyaq Coupé iV all-electric cars, with the RS models in this electric range being the most powerful Škoda cars ever, with a system output of 220 kW.

All-wheel drive in motorsport

Škoda has also enjoyed great success with all-wheel drive cars in motorsport. One of the most successful competition cars of all time, the Fabia Rally2 evo, was retired last year, replaced by the new Fabia RS Rally2. Based on the fourth generation of the Czech carmaker’s popular hatchback, the Fabia RS Rally2 has been endowed with the most modern and sophisticated technology permitted by the FIA rules for the Rally2 category. This package includes a robust all-wheel drive system with mechanical differentials on the front and rear axles. Again, the power of the specially developed 1.6 liter engine is transmitted to all wheels via a five-speed sequential gearbox. Four test drivers pushed the car hard over 10,000 kilometers during development of the new competition special. Škoda offers the car to private rally teams.