A working equipment arranged to be mounted to a vehicle, the working equipment comprising: - a movable arm for loading and unloading a load carrying object, such as a container, to/from said vehicle, wherein the movable arm has a first end connected to said vehicle and a second end arranged to connect the movable arm to the load carrying object during the loading or unloading; - a lift frame assembly comprising a lift frame with an attachment part arranged to be attached to the second end of the movable arm, a pair of upper connectors mounted at opposite sides of an upper part of the lift frame, and a pair of lower connectors mounted at opposite sides of a lower part of the lift frame, wherein said pairs of upper and lower connectors (20, 24) are adapted to attach said upper and lower parts (22, 26) of the lift frame to a corresponding upper part and lower part, respectively, of the load carrying object; characterized in that it further comprises: - an actuator system, arranged to operate movements of the working equipment; - a sensor system, arranged to monitor the movements of the working equipment, and - a control unit configured to generate control instructions to control the operation of the actuator system in response to a loading/unloading command for the loading and/or unloading of the load carrying object and sensor signals received from the sensor system, wherein the lift frame assembly further comprises a set of pivotable guiding structures arranged at opposite sides of the lift frame, wherein said guiding structures are pivotable about pivoting axes P close to the opposite sides of the lift frame, and that the control unit is further configured, during a lift frame alignment procedure, to generate an alignment control signal to move the guiding structures from retracted positions into closed positions where the guiding structures are in contact with vertical side surfaces of the load carrying object, wherein, during movement of the guiding structures from the retracted positions into the closed positions, the lift frame are forced to be pivoted in order to be aligned to the side surfaces of the load carrying object. - a movable arm for loading and unloading a load carrying object, such as a container, to/from said vehicle, wherein the movable arm has a first end connected to said vehicle and a second end arranged to connect the movable arm to the load carrying object during the loading or unloading; - a lift frame assembly comprising a lift frame with an attachment part arranged to be attached to the second end of the movable arm, a pair of upper connectors mounted at opposite sides of an upper part of the lift frame, and a pair of lower connectors mounted at opposite sides of a lower part of the lift frame, wherein said pairs of upper and lower connectors (20, 24) are adapted to attach said upper and lower parts (22, 26) of the lift frame to a corresponding upper part and lower part, respectively, of the load carrying object; characterized in that it further comprises: - an actuator system, arranged to operate movements of the working equipment; - a sensor system, arranged to monitor the movements of the working equipment, and - a control unit configured to generate control instructions to control the operation of the actuator system in response to a loading/unloading command for the loading and/or unloading of the load carrying object and sensor signals received from the sensor system, - an actuator system, arranged to operate movements of the working equipment; - a sensor system, arranged to monitor the movements of the working equipment, and - a control unit configured to generate control instructions to control the operation of the actuator system in response to a loading/unloading command for the loading and/or unloading of the load carrying object and sensor signals received from the sensor system, wherein the lift frame assembly further comprises a set of pivotable guiding structures arranged at opposite sides of the lift frame, wherein said guiding structures are pivotable about pivoting axes P close to the opposite sides of the lift frame, and that the control unit is further configured, during a lift frame alignment procedure, to generate an alignment control signal to move the guiding structures from retracted positions into closed positions where the guiding structures are in contact with vertical side surfaces of the load carrying object, wherein, during movement of the guiding structures from the retracted positions into the closed positions, the lift frame are forced to be pivoted in order to be aligned to the side surfaces of the load carrying object.