Power distribution control apparatus for four wheel drive vehicle

When vehicle behavior control systems such as VDC, TCS, ABS and the like are operative, a front-rear power distribution control apparatus for a four wheel drive vehicle can have an excellent convergence characteristic in vehicle behavior control by choosing a transfer clutch torque from a region of a predetermined table in which the power distribution control does not interfere with the behavior control of the vehicle behavior control system and by establishing the transfer clutch torque to a larger value with an increase of transfer input torque. When the vehicle is in an understeer or oversteer tendency, the convergence of vehicle behavior is further enhanced by correcting the transfer clutch torque in an increasing or decreasing direction.