Vauxhaull Insignia is still continuing its success as one of the UK’s best selling mid-size vehicles thanks to its fabulous design, refined engines and the variety of options and packages you can get for it. And now there’s a new one! Before this you could only have the Insignia 2.0- and 2.8 petrol with AWD, but now for the first time they are offering their adaptive 4×4 system with the 2.0-litre 160PS CDTi diesel engine as well.

The Vauxhall Adaptive 4×4 system, like all the other 4×4 systems these days, is very clever. It only kicks in when four-wheel-drive is necessary. For instance if your driving along normally in a dry freeway, the car becomes a full-on FWD, but with the first hint of loosing traction in any of the four wheel, the system engages and sends more power to the wheels with more grip. Like so it helps with the efficiency as well.

4×4 Insignia Toure Diesel also comes with FlexRide chassis and the electronically controlled rear limited slip differential (eLSD), so at least on paper it should be ab;e to handle like dream! And because it’s a diesel you also get great fuel economy. The only worry should be the power of this diesel unit, which at 160 PS is not bad, but it’s not enough grunt for a pleasant drive.

All-wheel drive electronics act as early-warning system

A big advantage of Vauxhall’s all-wheel drive system is that wheels don’t have to spin before the proper corrective measures are introduced. When the sensors detect a critical situation, it only takes around 80 milliseconds – the blink of an eye – for the system to send the required power distribution to the wheels. The power can be distributed seamlessly between the front and rear axle or between the rear wheels. In contrast to conventional mechanical all-wheel drives, the hydraulic controls enable lightning-quick reaction and intervention.

The all-wheel drive system constantly receives updates from three modules called Body Control Module (BCM), Engine Control Unit (ECU) and the ESP. The car’s system analyses the information and distributes torque individually to the wheels, as needed.

For ultimate stability and performance, the Adaptive 4×4 all-wheel drive system is equipped as standard with an electronically controlled Limited Slip Differential (eLSD). The eLSD electronically controls the distribution of torque between the left and right rear wheels, transferring rear axle torque to the wheel that has the most grip. While offering better traction in slippery conditions, the sophisticated operation of the Adaptive 4×4 improves stability in all situations

The Insignia 4×4’s power distribution travels from the front axle differential to a hydraulic Haldex multi-disk clutch, which electronically distributes the torque as required. This can be from zero to 100 percent between the front and rear axle. In the rear, power is distributed by a hydraulic multi-disk clutch which can transfer nearly 100 percent of the power to one rear wheel if required. This gives drivers the confidence that their Insignia 4×4 can still maintain safe traction even if three wheels are on sand or mud and only one rear wheel can find grip.

The modules receive their signals from sensors that capture yaw rate, acceleration, steering angle, wheel speed, throttle pedal position, engine speed and torque, and adapt power distribution to the driving situation based on this information. Even before take-off, the control module receives information on throttle pedal position and engine speed and is able to transfer torque between the front and rear axle to prevent the car losing traction.

Bad roads, rain and mud call for stability and control

Many drivers have experienced the feeling of picking up too much downhill speed, so they take their foot off the throttle only to realize their vehicle is struggling to follow the steering direction. The Insignia’s Adaptive 4×4 system uses a complex sensor system, to redirect power to individual wheels when the engine is slowing down (drag torque) as a result of releasing the accelerator. This allows drivers to steer more accurately and keep control of the vehicle.

Thanks to the many control options like torque and braking torque distribution and FlexRide damper control, the adaptive all-wheel drive system handles many critical driving situations without the need for ESP. which stays in the background as a ‘guardian angel’.

Front-wheel-drive employed where conditions permit

The Opel Insignia Adaptive 4×4 system not only helps out in tricky safety situations, it also detects when no external conditions require special intervention, such as travelling on a motorway. In this case the system switches off the rear-wheel drive system and reverts to front-wheel drive to reduce friction loss and save fuel.