In the PhD thesis we have studied the effect of different organic friction modifiers on wetting with oil and consequently on elasto-hydrodynamic friction reduction. The theoretical background shows that, currently, the role of wettability in tribological applications is still not fully understood, especially with regard to wettability with lubricating oils, which exhibit the so-called spreading wetting behaviour in contact with most metals. In this work, we have evaluated the wettability of steel with oil at 25 °C and 100 °C using static and dynamic wetting parameters. The results show that the dynamic parameters are more suitable for wetting characterization in real tribological applications than the static ones. The results of surface energies and Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy show that all tested additives adsorbed to the steel surface at both 25 °C and 100 °C, and that the adsorbed film significantly increases the oleophobicity of the surface. The Quartz Crystal Microbalance with Dissipation monitoring (QCM-D) results confirm that the tested additives adsorbed from oil on steel at both 25 °C and 100 °C, and that the adsorption is governed by the polarity of the additive. Variations in the molecular structure of the additive (number of polar groups, alkyl chain length, polarity of the functional head-group, saturation) also affects oleophobicity, the trends are the same at 25 °C and 100 °C, this influence being most evident with dynamic wetting parameters. The results of tribological tests in the elasto-hydrodynamic (EHD) lubrication regime at 25 °C and 100 °C show that the tested additives reduce the friction coefficient even under when the surfaces are completely separated by the lubrication film. The coefficient of friction decreases with increasing oleophobicity of the adsorbed film (larger advancing and receding contact angles). Only with the addition of organic friction modifiers to the base oil that have the ability to adsorb to the steel surface, we have reduced the coefficient of friction up to 12.4 % at 25 °C and up to 22.2 % at 100 °C, which presents an important technological contribution.