Oil analysis technique is used as predictive and proactive tools to identify the wear modes of rubbing parts and diagnose the faults in machinery. In this research the wear behavior of diesel engine based on condition data especially on oil analysis will be studied. For analyzing historical data, descriptive statistics will be used as data mining tool to find the relationship between condition factors of machine and its final status. Based on this relationship a specific baseline will be achieved specially for selected equipment in their specific condition. The selected equipment are divided in two major groups (plantation and forestry, general construction) based on their condition to show the effects of condition on wear behavior of same engine in different circumstances. As a result in this project, five different cases are analyzed and the origins of their problems are determined. In addition for each wear material in each condition a new baseline is made based on historical data and also with help of correlation analysis the most effective materials for each condition are identified.