Abstract: A vehicle transmission employs a pair of coaxial input shafts, one driven at fixed ratio and the other driven at an infinitely variable ratio through a hydrostatic transmission which relatively reverses direction of rotation. A single input-dual input planetary gear assembly couples the coaxial input shafts to an output shaft. The planetary gear assembly is made up of a reverse and low forward speed planetary gear set and a high forward speed planetary gear set connected together to provide a four element planetary gear assembly synchronously shiftable between low and high ranges and which provides torque multiplication throughout the speed range and produces the same direction of rotation of all four elements at substantially or at the same speed when operating at the maximum forward speed condition.

Abstract: .Badd.A power train includes an input means and an output means, the output means being operatively connected with a speed differential gear means. A first drive transmitting means including hydraulic transmission means is connected between the input means and the gear means. A second drive transmitting means is connected between the input means and the gear means, and means is provided for drivingly connecting and disconnecting the second drive transmitting means. The power train can be changed from a single drive path condition to a dual drive path condition and vice versa while maintaining a constant drive ratio between the input means and the output means. .Baddend.