The Adani Dahanu Thermal electricity Station (ADTPS) is a leading electricity producing facility in the country, having begun commercial operations in January 1996. ADTPS is distinguished for its technological innovation, outstanding international performance, and long-term sustainability, having received multiple important accolades that underscore its operational excellence. This paper details a successful case of implementing coordinated condition monitoring techniques at ADTPS, which effectively diagnosed an imminent foundation deterioration of the main reducer gearbox (GB) in the coal mill. The application of vibration FFT spectrum analysis was important in pinpointing the precise root cause of recurrent misalignment problems in the gearbox. The research identified irregularities in the foundation, facilitating prompt repair that averted further damage to the gearbox, motor, and related gear drive components. The advantages of this proactive diagnosis were substantial. The identification not only averted expensive downtime but also circumvented significant repair or replacement expenses, so ensuring the unit's ongoing reliability. This case study illustrates the essential function of vibration monitoring and FFT analysis in protecting plant operations. These strategies have averted prospective failures, so safeguarding the plant from significant financial losses associated with unanticipated breakdowns, maintenance expenses, and spare part replacements. Moreover, the enhanced reliability has guaranteed optimal plant availability for power generation, hence augmenting the plant’s total efficiency and performance.