Abstract: A variable ratio fluid-mechanical variable ratio drive apparatus (10) is described utilizing an axial piston, variable positive displacement pump (22), an axial piston, variable positive displacement motor (24); and an intermediate planetary gear set (16). The apparatus has an input drive shaft (35) connected to planetary gear carrier (20) for driving the planetary gear set. The pump (22) has a shaft (54) mounted coaxial to the input drive shaft (35) and is connected to a sun gear (21) to control the rotational speed of the sun gear (21). The apparatus has an output shaft (143) operatively connectable to a planetary ring gear member (18). The motor (24) is mounted coaxial and operatively connected to the output shaft for transferring torque therebetween. The pump (22) and the motor (24) are hydraulically interconnected to transfer fluid therebetween.