GKN Driveline has revealed the world’s smallest AWD disconnect system which boasts a 4% fuel consumption improvement over permanent AWD models.

Engineering conglomerate, GKN has revealed details of its world-first Disconnect All-Wheel Drive System for A-, B- and C-segment vehicle platforms (a world-first in that it’s the smallest AWD disconnect system). The company claims fuel consumption during steady-state cruising is improved by around 4% when compared with permanent all-wheel drive systems.

In a statement, Senior Programme Director Hannes Prenn said, “As global demand for smaller, more efficient SUVs continues to grow, GKN’s Disconnect All-Wheel Drive System will help open new markets. This compact new system enables manufacturers to offer customers more capable and dynamic vehicles with improved fuel-efficiency and CO2 emissions.”

According to GKN, it’s Disconnect All-Wheel Drive System includes a modified power transfer unit (a monoblock housing that fully integrates the propshaft’s constant velocity joint), linked to the transmission’s final drive differential. The PTU contains a fast-disconnect device and brake that can bring the all-wheel drive system to rest upstream of the PTU’s hypoid gears. An electro-mechanically actuated clutch (which is a development of the system in the Range Rover Evoque) located in the rear axle both biases drive torque and disengages the all-wheel drive system downstream of the hypoid gears to save fuel.

“A dedicated driveline control unit continuously monitors vehicle dynamics and environmental conditions, disconnecting the AWD system during steady-state driving speeds when the AWD function is not needed. If the driver or conditions require more traction, the AWD system reconnects within 300 milliseconds. An active torque biasing function provides precise control of the distribution of torque between the front and rear wheels, optimising traction, stability and performance. Torque vectoring between the individual rear wheels is also possible with the system and has already been introduced on the Range Rover Evoque,” a statement read.

Senior Vice President of Engineering, Rob Rickell, sai,: “With all production, engineering and software development in-house, GKN Driveline is the only supplier able to develop and supply such a tightly integrated all-wheel drive system. The result is the lightest, most compact and capable disconnect all-wheel drive system available in the market. The same hardware can support models built on a common platform but with different performance requirements. GKN’s software engineers fine-tune the electronic control to deliver specific brand characteristics.”