BMW 7 Series uses GKN lightweight sideshafts
GKN Driveline’s new lightweight VL3 constant velocity joint (CV Joint) system, which enables rear-wheel drive platforms to save more than 4 kg 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%.
Karl Berger, GKN Driveline Senior Director Product Technology of Constant Velocity Joints, said: “GKN already established the benchmark for rear CV Joints with our predecessor technology, but the VL3 sets the new level. 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 18 mm, the VL3 is an alternative for rear constant velocity sideshafts for medium working angles with low axial forces and improved minimum backlash. It uses a Monobloc Tubular Shaft and Face Spline connection to the wheel hub to achieve significant packaging and weight advantages as well as noise, vibration and harshness (NVH) behavior benefits.
GKN pioneered the CounterTrack principal on fixed joints starting in 2009 and the VL3 joint further builds on this success by introducing the technology on rear sideshafts. The VL3 joint uses a new 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.
Berger added: “GKN has pioneered the development of CV joints for more than 60 years. 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 optimizing power delivery from the engine to the wheels. We have also minimized backlash, which leads to a refined driving experience.”
The VL3 sideshafts system has recently been named as an Automotive News 2016 PACE Award finalist.