What is one of the first signs of bearing failure?

High bearing temperature is one of the first signs of bearing failure because it often indicates that the bearing is experiencing increased friction or inadequate lubrication. When a bearing begins to fail, it generates excessive heat due to the breakdown of its lubricating properties or the introduction of contaminants. This rise in temperature is typically a precursor to more severe issues, such as wear and tear, which can ultimately lead to complete bearing failure if not addressed promptly. Monitoring bearing temperatures is therefore crucial in preventive maintenance, as early detection of abnormal temperature increases can help in taking corrective actions before the situation escalates into more significant damage or a total breakdown.