At an oil-water boundary on a solid surface, the hydrophobicity of a solid surface can be represented by the displacement energy, which is dependent on the properties of the emulsifying agents. The tendency of oil to displace water can be estimated by considering the displacement energy. An interesting property of oilin-water (o/w) that has attracted the attention of tribologists, is their ability to form thicker hydrodynamic films than those expected from their apparent rheological properties. To study this phenomenon, experiments have been conducted on a specially designed viscometer rig, with different o/w concentrations. The rig is composed of a metal tube with straight and uniform parallel ground bore and droppers of PTFE material, which are allowed to descend at micro-clearances in the vertically positioned tube filled with the different o/w mixtures at uniform velocity. It is found that, even at oil concentrations as low as a few percent, higher viscosity values for o/w mixtures are obtained in the concentrated contacts in relation to their bulk values.