Abstract: A mixing car for transporting molten metals, comprises, a car undercarriage with a longitudinally elongated mixing vessel supported on the undercarriage at each end for rotation about a horizontally disposed longitudinal axis of the vessel. The support means at at least one end comprises a support bridge frame which is universally pivotally mounted on the undercarriage and is provided with journals on each side for accommodating a support roller shaft which is held in position in respect to the support bridge frame by an anti-rotation safety. The roller shafts include ends which extend outwardly from each longitudinal end of the bridge frame and hollow rollers are mounted on each projecting end of the roller shaft on suitable roller bearings. Interior support rollers are also provided which are affixed to the end of the shaft outboard of the roller bearings and which carry diametrically opposite rollers which engage and support the support rollers.