Reverse displacement axial piston motors

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Efficiency and performance

The Danfoss Reverse Displacement Motor (RDM) is a breakthrough in technological innovation and engineering.

The heart of the new technology is an integrated shift valve. When used in a fan drive application, triggers a series of cost-saving and efficiency-boosting advances.

Features and benefits

Elimination of the directional control valve increases machine efficiency

Reducing the need - or even eliminating - the HIC block creates a higher performing system

Save money and assembly time by using fewer components such as hoses and valves saves money and assembly time

Freeing space in the engine compartment allows for innovative design

Eliminating the heat generated by traditional reversing systems keeps your machine running smoothly

Draws less power, so more power can be used for work

Optimize fan drive solutions with the RDM and the new Series 45 Fan Drive Control (FDC). When used with the RDM, FDC maximizes efficiencies and performance in an open circuit reversing fan drive system.

The Danfoss Reverse Displacement Motor is just one of the many product innovations and system solutions created by our continuous improvement and re-engineering efforts.

The directional control valve is eliminated, and the shift valve integrated into the Danfoss Reverse Displacement Motor (RDM). This reduces system design variables and creates new possibilities for engineers.

The Danfoss RDM's space-friendly design was made possible by removing components. Less power use in the motor means more power is available for work. This means the less obstacles and a more optimized engine compartment for engineers and operators. 


  • The innovative design means the RDM generates less heat and uses up to 10% less power than other solutions. Operators will feel the difference as they have more power to work with
  • Few components, a reduced need for, or even the elimination of, the HIC block, and compact motor design combine to free up more space in the engine department


Using the Danfoss Reverse Displacement Motor (RDM) in a fan drive application offers reduced complexity. This pays off in several ways for product managers.

The Danfoss RDM lets you tap into the power of simplicity to create greater assembly efficiencies and reduced aftermarket costs. That means fewer headaches and greater profitability.


  • Fewer components in the hydraulic system means decreased assembly time
  • Common platforms across all displacements create efficiencies by removing the need for different tools, assembly processes and test methods
  • Less complexity through the hydraulic circulation system holds the promise of lower aftermarket support costs
  • PLUS+1® compliant for seamless integration into existing systems
  • Faster time to market with lower design and build times 


Perhaps the only think more impressive than this hydraulic system solution is the ability to reduce your costs. At the same adding Danfoss quality, reliability and service. 

For purchasing managers, selecting the Danfoss Reverse Displacement Motor (RDM) means:

Features and benefits

  • Reduced total cost of the hydraulics circuit by removing and simplifying components 
  • Working with a proven company that meets delivery schedules with high-quality, durably built products 
  • Exceptional customer service and support 
  • A common platform across all motor sizes—including three displacements in the same compact motor size—allows for standardization


The Danfoss Reverse Displacement Motor (RDM) is a smarter solution for powering today's hydraulic systems. It will enable your company to save money on the front end and enhance your brand over the long term. What will you gain without making a sacrifice?

Features and benefits

  • A breakthrough solution that's grounded in proven motor technology and eliminates efficiency-losing components
  • Rugged design that includes a tapered shaft and dust seal, high-capacity bearings, anti-cavitation and shock valve for dusty and dirty applications such as agriculture, forestry and construction
  • A simplified hydraulic circuit builds your brand by decreasing maintenance and repair costs and increasing useable power
  • The Danfoss commitment to product service, quality and support. Get the right product at the right time.

With the RDM, Danfoss renews its commitment to engineering tomorrow. This remarkable innovation is designed with power, space and performance in mind. It will enable OEMs to meet the world's growing demand for hydraulic system solutions to power tomorrow's machines. We invite you to partner with us for access to Danfoss engineers and the application-specific knowledge you need.


Engineered for power, space, and performance

Engineered for power, space, and performance

The Danfoss Reverse Displacement Motor (RDM) is a breakthrough in technological innovation and engineering.


Type Name Language Valid for Updated Download File type
Promotion material RDM Axial Piston Motor Brochure English Multiple 13 Sep, 2016 20.6 MB .pdf
Promotion material RDM Brochure Chinese (CN) China 18 Oct, 2018 982.6 KB .pdf
Data sheet Reverse Displacement Motor (RDM) Data Sheet English Multiple 10 Mar, 2015 561.4 KB .pdf
User guide Reverse Displacement Motor (RDM) Technical Information Manual English Multiple 10 Mar, 2015 3.0 MB .pdf

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