Abstract: A process for re-refining used lubricating oil (ULO), much of which is used motor oil (UMO) relies on more rapid heating, turbulent flows, higher peak temperatures, to achieve rapid thermal cracking, even including metal-bearing additives without catalysts, compared to conventional refining of crude oil and conventional recycling processing of UMO. By thermally cracking this way and scrubbing with recycled, processed liquids from the flow stream, a process readily removes metal-bearing hydrocarbons in typical lubricating oil additives. Those bonded metals consigned to heavy fraction “bottoms,” are commonly non-removable by other recycling schemes. Long chain polymers including paraffins are broken into lighter hydrocarbons with properties typical of fuels containing olefins, naphthenes, and the like. Data and analysis reveal low solids, effective metal removal, comparatively low viscosity and boiling points, and greatly reduced sulfur content in fuel and oil products resulting.