Snow-clearing trailer (1) having a chassis (5) extending longitudinally in a chassis direction (I-I) and having a drawbar (9). Pivoting means (11) allow the selective pivoting movement of the chassis (5) and the drawbar (9) with respect to one another. A drawbar locking bar (12) of fixed length can be attached to the drawbar (9) and to the chassis (5) so as to immobilize the drawbar (9) on the chassis (5) in a transport position. Detection means (13) generate an attachment signal when the drawbar locking bar (12) is attached to the drawbar (9) and to the chassis (5). The detection means (13) and disabling means are arranged in such a way that when the detection means (13) generate an attachment signal, the disabling means prevent any actuation of the pivoting means (11).