An attachment system for an implement which is arranged to be connected, at least in a working position, to a three-point implement linkage on an implement carrier, and which is provided with at least one wheel which is arranged to support the implement in the transport position of the implement, characterized in that connection pins which are arranged to be connected to the lower three-point connectors (211a, 211b) of a three-point implement linkage are arranged to be adjustable between a retracted first position, wherein a coupling beam is locked to an implement frame in a rotationally rigid manner, or in a position in which a limited pivoting is allowed, and an extended second position displaced in a direction away from an implement frame, wherein the coupling beam is extendedly pivotal relative to the implement frame, wherein the attachments system comprises coupling means (126, 128, 125; 1211, 117; 14, 141, 142, 143) arranged to connect the coupling beam to the implement frame in a rotationally rigid manner, change from rigid to free pivotal state of the coupling beam is obtained by displacement of the connecting pins forward in relation to the implement frame thereby affecting the coupling means (126, 128, 125; 1211, 117; 14, 141, 142, 143) such that a larger distance between the connecting pins and the implement frame is obtained after unlocking locking means (127, 114; 115; 13, 143c); and wherein a) the coupling beam connected to the connection pins is fixed, to the implement frame in said first position, and the coupling beam in said second position is pivotal around a vertical pivot axis in the implement frame, the connection pins being arranged in end portions of coupling arms attached to end portions of the coupling beam and adjustable between a retracted position wherein the coupling beam is partly pivotal or rigidly locked, and a position projecting forwards wherein the coupling beam is extendedly pivotal, or b) the coupling beam which is arranged to be connected to the lower three-point connectors (211a, 211b) of the implement carrier, is releasably connected to a lower, forward frame portion of the implement, and a middle portion of the coupling beam is provided with a vertical pivot axle in engagement with cut-outs in the implement frame, or c) a coupling beam, which is arranged to be connected to lower three-point connectors (211a, 21b) of the implement carrier, is releasably connected to a lower, forward frame portion of the implement, and two foldable drawbars (14a, 14b) connect a middle portion of the coupling beam to the lower, forward frame portion, the drawbars (14a, 14b) including several pivot joints (141, 142, 143; 141, 142, 143a, 143b) provided with substantially vertical pivot axes. a) the coupling beam connected to the connection pins is fixed, to the implement frame in said first position, and the coupling beam in said second position is pivotal around a vertical pivot axis in the implement frame, the connection pins being arranged in end portions of coupling arms attached to end portions of the coupling beam and adjustable between a retracted position wherein the coupling beam is partly pivotal or rigidly locked, and a position projecting forwards wherein the coupling beam is extendedly pivotal, or b) the coupling beam which is arranged to be connected to the lower three-point connectors (211a, 211b) of the implement carrier, is releasably connected to a lower, forward frame portion of the implement, and a middle portion of the coupling beam is provided with a vertical pivot axle in engagement with cut-outs in the implement frame, or c) a coupling beam, which is arranged to be connected to lower three-point connectors (211a, 21b) of the implement carrier, is releasably connected to a lower, forward frame portion of the implement, and two foldable drawbars (14a, 14b) connect a middle portion of the coupling beam to the lower, forward frame portion, the drawbars (14a, 14b) including several pivot joints (141, 142, 143; 141, 142, 143a, 143b) provided with substantially vertical pivot axes.