seals are deformed asymmetrically according to circumferential direction by shearing stresses applied by the lubricating film. In fact, all simulations and experiments showed that a successful seal operates with a maximum shear displacement closer to the liquid side of the seal than to the air side . This action transforms the asperities into mini viscous pumps , thereby producing reverse pumping as described by Stakenborg [5]. In order to improve the rotary lip seal performance , new gen- erations of grooved lips [6] and shafts [7,8] have emerged . The first numerical model [6] has been performed by assuming a stationary sleeve lip textured and arigid , smooth rotating shaft. The results have shown the optimum parameters of the lip surface texturing for a minimum friction coefficient. Subsequently, Jia et al. [7] developed a theoretical model to predict radial lip seal performances of a textured shaft with geo- metries defined by a simple analytical function. Generally, the model has shown acceptable accuracy with experiments. In addition, the groove geometry effect was investigated on reverse pumping. It has been proved to be a function of the groove angle, depth , density and shaft speed. Recently, the same authors [8] have experimentally and numerically demonstrated that a shaft surface finish with oblique grooves can generate substantial pumping. This result was proved by a new approach, where Reynolds equation was resolved with a realistic textured shaft. The groove geometry was measured on a representative shaft froma3-Dmicrograph.