The speed reducer of the self-feeding mixer truck decelerates the speed output by the motor in the hydraulic system and transmits it to the mixer drum. The operating mechanism controls the rotation direction of the mixing drum so that it rotates forward during the feeding and transportation process, and rotates in the reverse direction when discharging, and controls the rotation speed of the mixing drum.

The mixing device of the self-feeding mixer truck is mainly composed of a mixing drum and its auxiliary supporting parts. The mixing drum of the self-loading mixer truck is a loading container for concrete. When rotating, the concrete moves along the spiral direction of the blades, and is mixed and stirred during the continuous lifting and turning process. During the feeding and transportation process, the mixing drum of the self-loading mixer truck rotates forward, and the concrete moves inward along the blades; when discharging, the mixing drum reverses, and the concrete is discharged outwards along the blades. The blade is the main part of the mixing device, damage or severe abrasion will cause uneven concrete mixing. In addition, if the angle of the blade is unreasonably designed, it will also cause segregation of the concrete. The main function of the cleaning system is to clean the mixing drum, and sometimes it is also used to mix dry materials during transportation. The cleaning system also cools the hydraulic system.