GKN Driveline’s new lightweight VL3 constant velocity joint (CV Joint) system, which offers OEMs the ability to reduce the weight of rear-wheel drive platforms by more than 4kg of weight, has been selected by BMW to launch on the all-new 7 Series.
GKN’s new VL3 CV joint increases torque capacity by up to 27% with no increase in packaging size. Available in four sizes, automakers alternatively have the choice of maintaining torque capacity but reducing package size by approximately 10%.
“GKN already established the benchmark for rear CV Joints with our predecessor technology, but the VL3 sets the new level,” explained Karl Berger, GKN Driveline senior director Product Technology of Constant Velocity Joints. “We have developed a CVJ that is lighter, more efficient, stronger and delivers more torque in smaller packaging. The VL3 joint helps automakers achieve a refined, luxury driving experience. We are delighted that it is debuting on the BMW 7 Series.”
With a plunging distance of 18mm, the VL3 is suited to a rear constant velocity sideshaft for medium working angles with low axial forces and best in class minimum backlash. It uses a Monobloc Tubular Shaft and Face Spline connection to the wheel hub to, as GKN claim, achieve ‘significant packaging and weight advantages as well as noise, vibration and harshness (NVH) behaviour benefits’.
The VL3 joint uses a new and innovative track geometry with four pairs of opposed ball tracks instead of three, which enables it to transmit more torque to wheels within the same packaging space. The joint is further enhanced through the use of a diaphragm boot sealing system, instead of a standard boot and cap, which helps reduce axial packaging, grease volume and weight.
“GKN has pioneered the development of CV joints for more than 60 years,” added Berger. “These latest innovations offer improvements in every area of importance for automakers, including strength, endurance, efficiency and weight, helping to produce a dynamic driving performance and optimising power delivery from the engine to the wheels. We have also minimised backlash, which leads to a refined driving experience.”