An installation for treating articles, especially vehicle bodies, comprises at least one treatment zone, in particular a bath containing a treatment liquid, into which the articles are introduced. The articles are conveyed through the installation in a continuous or intermittent translational movement. To this end, the installation comprises at least two transport carriages combined to form a pair, which in turn each comprise a running gear and at least one swivel arm, which is connected to the respective running gear so as to be swivellable about a first pivot pin and with which a supporting structure for the article to be treated is connected so as to be swivellable about a second pivot pin. The unit includes the two transport carriages effecting a correlated movement actually has six degrees of freedom of motion, wherein drives are provided for at least three of these degrees of freedom of motion.