A wheel carrier assembly (10) of a machine for agricultural use, such as a tractor, has a drive axle (2) and steering wheels. The wheel carrier assembly (10) includes a constant-velocity joint (100) for the connection, upstream, of the wheel carrier assembly (10) to the transmission. The assembly includes, downstream, a rotation shaft (101) for the rotation of the wheel assembly. A disc brake device (200) controls the braking of the wheel assembly. A gear reducer (300), connects to the wheel assembly and to the rotation shaft (101). The disc brake device (200) is operationally connected to the rotation shaft (101) so that the braking action is applied directly on the rotation shaft, upstream of the gear reducer (300).