Geareducer® - M Series
OVERVIEW Marley M Series Geareducers are designed and manufactured to directly replace Amarillo brand gear drives in cooling towers for power and industrial applications. In shape and function, their design goes beyond standard AGMA requirements – both to maximize air movement through the tower and to minimize maintenance requirements.


The Marley M Series Geareducer is designed to directly replace gearboxes found in non-Marley cooling towers, specifically Amarillo gear drives. The footprint of the M Series matches comparable Amarillo gear drives, eliminating the need to replace or add other tower components such as the fan hub, driveshaft or adaptor plate. Simplified replacement means the M Series offers the customer significant savings in components and labor costs.

Combining the proven longevity and performance of Marley’s robust housings and bearings with modern seal enhancements and built-in vibration transducer mounting, the comprehensive M Series eliminates the need for additional pumps, filters or coolers to run properly. External cooling fins and large internal oil passageways both contribute to keeping the M Series running cool and prolonging oil life. It also optimizes cooling tower fan performance with minimal noise, transmission losses and vibration levels. The M Series is a top-tier, advanced alternative to speed reducers such as those produced by Amarillo.

Marley Geareducers withstand the extreme temperatures and humidity of cooling tower environments. And, since we warrant not only the Geareducer, but the thermal performance of the cooling tower it supports, the design, engineering, and manufacture are taken very seriously. This results in more reliable operation and longer life cycle - a superior solution for large industrial and power plant applications.


Genuine Marley OEM parts are precision-engineered to provide you with a reliable product. While other suppliers may offer parts at an initial savings, you risk lowering performance — and losing FM and CTI ratings. Marley OEM parts provide the durability you can trust because we design and manufacture them exclusively for cooling towers.

With plant operation relying on your cooling tower performance, it’s important to select the parts that are among the highest quality available — Marley OEM parts.

Featured Video:

Marley M Series Geareducer Install
  • Designed to fit Amarillo footprint

  • No oil pump, filter, or cooler needed

  • External cooling fins

  • Large internal oil passageways

  • Double row interstage bearings

  • Premium Inpro seal at input shaft

  • Output shaft sealed with maintenance-free labyrinth ring

  • Minimum L10a service life of 100,000 hours for all bearings

  • Timken tapered roller bearings


Marley Cooling Tower Parts