Studies of the physicochemical characteristics, group, and fractional composition of low-viscosity base oils with various nature were carried out. The influence of the composition of these oils on their low- and high-temperature characteristics was studied. Studies of the influence of the nature and composition of the dispersion medium on the physicochemical properties of low-temperature greases (LTG) thickened with lithium soap of stearic acid have been carried out. The possibility of expanding the operating temperature range and improving the antiwear properties of low-temperature greases through the combined use of low pour point mineral oil and high-index hydroprocessing oil has been found out. For the first time, the ability to predict the viscosity-temperature and tribological characteristics of lithium LTG based on standard methods for analyzing base oils are established.