The first term describes the normal traction due to the hydro- dynamic pressure p, and n is the outer normal to the lubricated boundary γl in the deformed configuration. The second term is the shear (friction) stress due to the Couette flow associated with the tangential relative velocity Δu. The last term is the shear stress due to the Poiseuille flow induced by the pressure gradient. It is well known that Eq. (19) may overpredict the shear stresses in the cavitation zone, see [7]. As a remedy, the Couette shear stress in Eq. (19) can be multiplied by a term ð1 λÞ so that the shear stress is reduced in the cavitation zone (for λ 4 0). However, as shown in Section 4.1, this has a negligible effect on the predicted overall friction coefficient.