Concrete mixer truck is a vehicle specially designed for the transportation of concrete for construction. Motive power is produced by the power takeoff then passed to the hydraulic pump. The hydraulic pump produces hydraulic energy which is transmitted to hydraulic motor for conversion into kinetic energy. This energy is then transferred to the mixing drum through the effect of decelerating the speed of rotation. Users can adjust the angle of the hydraulic pump servo handle to control the rotating speed and the positive or negative rotation of the mixing drum. This facilitates charging, stirring, mixing, and discharging operations.