Abstract: The invention relates to a method for measuring large components, especially the body of rail cars, which is characterized by the following features: a) producing a stressfree position of the large component in which it is not buckled, by means of a mechanical corner force measuring device, b) producing a reference position of the large component, likewise using a corner force measuring device, c) measuring the z dimensions of the large component using an electronic, self-leveling all-round laser and laser receivers, said laser describing a horizontal plane and the receivers which are disposed on the large component or on the measuring adapters automatically searching the laser plane, and d) measuring the x dimensions and the y dimensions of the large component using a tachymeter.