Semiarba automobilului se mai numește șischimbatorul de viteze, which connects the differential with the drive wheels. The schimbatorul de viteze is the shaft that transmits torque between the gearbox reducer and the drive wheels. There is a universal joint (U/JOINT) at the inner and outer ends of the shaft, which is connected to the reducer gear and the inner ring of the hub bearing through the spline on the universal joint.
Theschimbatorul de vitezetransmite puterea de la diferențial la roțile motoare stânga și dreapta.