A method is provided for evaluating a multiplicity of lubrication quality parameters. For a particular lubrication system, a parameter profile is designated to define all the measurable parameters to be monitored. Each parameter in the profile is assigned to single category respective to WEAR, CHEMISTRY and CONTAMINATION. Parameter values are proportionalized in a finite number of increments between acceptable and unacceptable limits. The worst case parameter of a category is selected to represent that category on a 3-axis, Cartesian graph for placing a data point along the respective category axis. Three data points respective to the three axes are linked with a triangular plane, the area of which is representative of the system quality state.