An attempt is made to formulate a thermohydrodynamic model of fluid-film lubrication that is valid in turbulent flow regimes. The model considers the flow to be a small perturbation of turbulent Couette flow. The modified Reynolds equation is obtained for the turbulent flow and the integro-differential energy equation makes the turbulence analysis easier by replacing the conductive terms in terms of the convective boundary conditions at two solid surfaces. Sample results applying the perturbation method agree well with available experimental data and theoretical methods.