An overhead conveyor system for transporting articles, especially for transporting vehicle bodies, in a surface treatment line comprises at least one transport carriage which has a fastening device to which at least one article can be fastened. The transport carriage can be displaced along a track carrying it by at least one drive means. The fastening device is received so that it can be rotated about a vertical axis of rotation. The invention further relates to a dip coating line comprising at least one dip-coating tank which can be filled with a treatment liquid, into which tank articles to be treated can be dipped. The dip coating line comprises a conveying system which displaces the articles to be treated towards the dip-coating tank, into the interior of the dip-coating tank, out of the dip-coating tank and away therefrom.