Abstract: A process for conveying vehicle bodies through a treatment tank for the surface treatment of the vehicle bodies, where the liquid of the treatment tank offers only a slight immersion resistance to the vehicle bodies during immersion and the flow velocities of the liquid relative to the submerging and emerging vehicle bodies are kept low. Prior to their introduction into the treatment tank the vehicle bodies are transferred from a standard position, in which window openings of each vehicle body are arranged above the floor pan of the vehicle body, into a headfirst position, in which the window openings of each vehicle body are arranged beneath the floor pan of the vehicle body. The vehicle bodies are subsequently introduced into the treatment tank in the headfirst position, conveyed through the treatment tank and brought out of the treatment tank again in the headfirst position.