Abstract: In these days condition monitoring plays a main role in many of the industries. Lubricantsare essential and expensive components of machine systems needing sampling, analysis and monitoring. Monitoring can be either performance testing or oil condition monitoring or vibration analysis. Hear wear debris analysis and vibration analysis plays a curtail role in the maintenance of the cooling tower. Components of the gear box fail without proper maintenance. For the reduce of the heavy expenses analysis is done. Key component of the cooling tower fan is the gearbox. Maintenance of gearboxes is difficult and expensive, given the location and therefore condition monitoring techniques have been applied to detect common failure mechanisms. Future condition monitoring may be possible using low cost on-line techniques. With these oil analysis and vibration techniques, monitoring has been done and gear box failures has been detected.