For quite awhile, BMW has been disappointing many consumers by only offering limited slip differentials on their M-badged models. Competitors such as Lexus and Infiniti have at least offered LSD options on their vehicles, but BMW's argument is that their traction control system is sophisticated enough to fight wheel slippage rendering the extra cost for an LSD unnecessary. But it looks like that long-standing policy at the German automaker will change in the very near future.
The latest news out of GKN Driveline and ZF Friedrichshafen AG is that they have joined forces to produce a torque vectoring system that will be implemented by BMW. The system utilizes two electronic torque managing units that are essentially clutch type differentials, with the plate pressure controlled by voltage supplied to two electric motors. It will be able to independently adjust the torque split between two wheels, without the need for wheel slippage to occur initially. The technology is being dubbed VectorDrive and it's configurable for AWD and RWD vehicles. It's about time BMW joined the bandwagon in moving away from the open rear differential.
Catch the official press release after the jump.
[Source: Automotive News]
PRESS RELEASE:GKN Driveline and ZF Torque Vectoring cooperation CTI Symposium, Berlin
Berlin, Germany 4th December 2007
GKN Driveline and ZF announce an extended cooperation in the field of torque vectoring systems. The cooperation agreement covers the joint development, manufacturing and marketing of torque vectoring systems in rear axles for rear and all wheel driven vehicles.
Mechanically this agreement includes two torque vectoring units flanged to the final drive, and two electric motors which drive the brakes to operate the torque vectoring units. The motors are controlled by a central ECU. The software, which communicates with the vehicle controller, ensures that the vectoring torque requirements dependant on the driving condition of the vehicle are realised by the system.
The first production application is planned for BMW, already announced as being ZF's VectorDrive. The Torque Vectoring hardware units produced by GKN Driveline will be supplied to system leader ZF, who is responsible for the final assembly of the system and the supply of the electric motors, the control ECU and programming, and the delivery of the EOL-tested units to the customer.
"The joint development is a significant step forward that allows us to bring the specific competences and know-how of our two companies together, develop cutting edge, high performance driveline technology and make it available to our customers as broadly and competitively as we can," said Graeme Walford, Managing Director of GKN Driveline Torque Technology.
Commenting on the announcement, Robert Paton, Managing Director for ZF's Axle Drive Division said: "We have an attractive 'modular' system concept that is ready for application and specific development with the OEMs. BMW will be the first, but we have already begun talking to other customers and are excited by the prospects for this cooperation technology. "