Abstract
The presented contribution deals with the comparison of selected ecological oils of the same viscosity class in terms of wear of the sliding bearing B 60 M4 as part of the matched sliding pair lubricated by ecological lubricant. The wear of the sliding bearing is monitored using the parameters; the change of geometric tolerance cylindricity having the most indicative capability about the size and location of wear. The second parameter is weight loss, and the third parameter is the change of surface roughness at the contact point of friction elements. Results are statistically processed and presented in the form of graphs and tables.