The four-wheel drive system operates by constantly receiving data via the high-speed CAN databus from the Electronic Stability Program (ESP) about the number of revolutions of each wheel, steering angle and accelerator pedal position. This information is continuously analyzed. Under normal conditions, all propulsion power is distributed to the front wheels and the rear axle clutch is therefore open. However, if the electronics recognize a need for action due to altered traction conditions, the torque is distributed seamlessly between the front and rear axle within 100 milliseconds. All propulsion ratios between full front-wheel drive and 50:50 distribution to both axles are possible.

To activate the rear axle, the control unit directs electricity to the electromagnetic pilot coupling's magnetic coil. The resulting magnetic field activates an armature in the coupling. A ball-ramp system acts as an additional power booster, while compressing the wet multidisk clutch. The higher the pressure on the main coupling, the more power is distributed to the rear axle.



Chassis

A Star Both On and Off the Road

- Intelligent four-wheel drive for balanced handling
- Sophisticated chassis concept with four-link rear axle
- Extensive ESP functions increase safety reserves

With its agile handling, precise speed-dependent power steering, firm, electronically networked chassis and active four-wheel drive, the Antara is designed for primarily on-road use. The new crossover was tuned by Opel chassis experts on various roads, including GM test centers in Pferdsfeld and Dudenhofen in Germany, as well as Millbrook in the United Kingdom. During development, the prototypes covered over five million kilometers worldwide. The Antara boasts additional dynamics, comfort and active safety thanks to the CAN Bus networking of all driving dynamics systems, such as ABS, Cornering Brake Control (CBC), ESP, Active Rollover Protection (ARP), Traction Control (TC), Descent Control System (DCS) and electronically controlled four-wheel drive differential.

The McPherson strut suspension in front and a four-link axle in the rear are similar to the chassis concept of the Opel Vectra and Signum models. The unusually long wheelbase (2707 mm) and wide track (front/rear 1562/1572 mm) are also key factors in the Antara's dynamic and comfortable handling.


Active four-wheel drive system ensures traction

The Antara's intelligent four-wheel drive system activates the rear wheels quickly and seamlessly via an electronically controlled differential for optimal traction when needed. Under normal conditions, the Antara is purely a front-wheel drive car.

However, if the electronic control unit detects a need for more traction, for instance on a slippery road, drive can be distributed between the front and rear wheels at a ratio of up to 50:50. Key elements are two clutches - one electromagnetic pilot and one hydraulic wet multidisk. In addition to monitoring wheel slip, the system's electronic central unit also processes a range of other information such as accelerator pedal position, engine rpm, vehicle speed, yaw rate and steering angle.


Dynamic and agile despite high ground clearance

The new Opel Antara's front suspension is mounted on a stable subframe which ensures precise wheel alignment and high lateral rigidity. Large-capacity damping elements isolate the front axle and steering from the body, keeping vibration and road impact well away from the vehicle interior.

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