This study addresses the mechanisms that distress a jlatjaced thrust washer bearing system. This washer bearing system sepa rates a helical gear and its carrier within a gearset. It was found that the bearing can experience distress by the combination of rotational speed, axial load, and the sequence and rate of their application. Distress is defined as a sudden rise in the real-time frictional torque and temperature.
The various tests suggest the presence of hydrodynamic effects at cenain rotational speeds and axial load combinations marked by decreases in the calculated effective coefficient of friction with decreases in velocity. In the tested cases, a distinct increase in the coefficient of friction occurs at the instant of distress.