A transfer case is provided for a vehicle having front and rear axles. The transfer
case includes a planetary gear set with first, second and third members. The first
member is continuously connected with the front axle and the second member is continuously
connected with the rear axle. An input shaft is selectively connectable with the
first, second or third member. The transfer case provides rear-wheel drive when
the second member is connected with the input shaft, all-wheel drive when the third
member is connected with the input shaft, and front-wheel drive when the first
member is connected with the input shaft. It is important that the specific members
of the planetary gear set be chosen so the absolute value of the torque of the
third member is equal to the sum of the absolute value of the torques of the first
and second members.
