A vehicle drive unit, for quickly recovering a grip even if a wheel slips,
in which in a slip state or at a time when the slip state is going to be
generated, by pulsating a torque applied to the wheel, an angular
velocity W of the wheel is changed so as to change the slip ratio S close
to a slip ratio at which a friction coefficient becomes maximum, and
thus, an average of a friction coefficient .mu. is enlarged and an
average of a vehicle driving force F generated by a wheel is enlarged.
Since the vehicle driving force is enlarged, the vehicle is accelerated
and is easily gripped. Further, in a grip state or at a time of traveling
at a high velocity, a vibration and an undesired sound are suppressed by
doing away with the torque pulsation or making the fluctuation band of
the torque pulsation small.