Abstract
The variation of traction coefficient with sliding speed for 26 lubricating oils whose flow properties had already been determined was measured with a two-disk machine. The maximum traction coefficient was correlated with the flow properties. It was found that the activation volume for viscous flow gave a good linear relation with the maximum traction coefficient. The linear relation is useful in rough estimation of maximum traction coefficient from the chemical structure of lubricating oil. The flow activation enthalpy and the shear relaxation time could not be correlated with the maximum traction coefficient.