Active Transfer Case Controls

Controls for the NV245 transfer case active clutch (torque biasing device) are located in the Final Drive Control Module (FDCM) and communicated on the CAN C bus. The FDCM monitors wheel speeds at the front and rear axles to detect wheel slippage. A complete vehicle dynamics model calculates slip at each tire for given vehicle-operating conditions. The clutch pack in the transfer case is engaged to minimize the speed difference between the front and rear axle, resulting in torque transfer to the axle with higher traction. The electronically controlled wet clutch pack uses an electric motor to actuate a sector plate. The sector plate actuates a clutch lever that applies normal force to the multi-disc wet clutch pack bridging the differential. The clutch discs are alternately splined to the front and rear driveshafts. When normal force is applied to this clutch pack, torque is transferred to equalize speed differences between front and rear axles.