The article deals with the use of the linearization method to take into account the stochastic nature of factors affecting the life of bearings. In addition, we should pay attention to such factors as the degree of contamination and viscosity of the lubricant, as well as the properties of the material from which the bearing parts are made. The developed method allows estimating the degree of influence of these factors on the bearing life. In order to adapt the graphical dependencies to the physic-probabilistic approach, Lagrange interpolation polynomial is used, which allows obtaining the calculated dependencies and automate the resource calculation. The linearization method makes it possible, if necessary, to simplify the mathematical model, neglecting the arguments that have minimal impact on the calculation result.