The invention provides a tool for moving a drivetrain component in a nacelle of a horizontal axis wind turbine, the nacelle comprising a nacelle structure, the component being connected, in operation of the wind turbine, to a rotor of the wind turbine, the tool comprising at least drive unit for moving the component in relation to the nacelle in a direction parallel to the rotational axis of the rotor, and a plurality of position adjustment devices adapted to be located between the nacelle structure and the component, and distributed so that rotational movement of the component can be provided by coordinated control of the position adjustment devices.