RE241578 RE241577 John Deere Tandem Hydraulic Pump 45cc 200bar

Product Overview

The RE241578 and RE241577 are John Deere tandem external gear pumps for tractor hydraulic systems, serving as the main hydraulic pump to supply fluid power to both the steering system and the hitch/lift system. The RE241578 main pump has a displacement of 45 mL/rev (configured as a 32+13 cc dual pump group), while the RE241577 features a 25+13 cc dual pump group configuration. Both share compatible mounting flanges, port layouts, and drive interfaces, allowing selection based on specific tractor models.

These pumps fit John Deere 1054, 1204, 1354, 1404, and 6603 medium tractors, compatible with 4045 and 6068 series engines. The external gear pump design with straight involute tooth profile delivers high efficiency, excellent impact resistance, low noise, and strong contamination tolerance.

Manufactured to exact John Deere OEM specifications, every unit features JD standard mounting flanges and interfaces fully consistent with the original pump for true drop-in interchangeability — no piping or coupling modification required. Each pump undergoes 100% simulated operating condition testing before shipment, covering rated pressure loading, flow verification, and housing sealing integrity.

Technical Specifications 

• Model: RE241578 (Main Hydraulic Pump) / RE241577 (Main Hydraulic Pump)

• Cross-Reference: RE241577 (RE241578 cross-reference)

• OEM Internal Part Number: 25A32/13X578JD (RE241578) / 25A25/13X577JD (RE241577)

• Pump Type: External gear pump, tandem pump group

• Displacement (RE241578): 45 mL/rev (32+13 cc dual pump group)

• Displacement (RE241577): 25+13 cc dual pump group

• Rated Pressure: 16 MPa (160 bar)

• Maximum Intermittent Pressure: 20 MPa (200 bar)

• Maximum Speed: 2,500 rpm

• Rated Flow (RE241578): 90–95 L/min

• Rotation Direction: Left-hand (counter-clockwise, viewed from shaft end)

• Mounting Flange: JD standard flange mount

• Net Weight: Approx. 12.6 kg

• Recommended Hydraulic Fluid: ISO VG46 hydraulic oil

• Compatible Engines: 4045 series, 6068 series

• Compatible Tractor Models: 1054 / 1204 / 1354 / 1404 / 6603 / 0904

Key Technical Advantages

1. Integrated Tandem Pump Design: The RE241578/RE241577 utilize a tandem gear pump structure integrating two independent gear pump groups within a single housing, supplying separate circuits for the main hydraulic system and steering system. This tandem design eliminates the need for external flow divider piping, reduces connection points and potential leak paths, and saves installation space in the engine compartment.

2. Precision-Machined External Involute Gears: Gears use a straight involute tooth profile with precision ground tooth surfaces for high contact accuracy. The involute profile provides a long meshing length that effectively reduces flow and pressure pulsation for smooth, low-noise operation. High-precision clearance between gears and housing ensures high volumetric efficiency and stable flow output under medium-to-high pressure conditions.

3. High-Strength Cast Iron Housing with Contamination Resistance: The pump housing is manufactured from high-strength cast iron with excellent rigidity and vibration resistance, capable of withstanding shock and vibration loads encountered in tractor operations. The external gear pump design is inherently insensitive to oil cleanliness, with strong contamination tolerance suitable for dusty field and construction site environments.

4. John Deere Drop-In Interchangeability: The RE241578 and RE241577 feature JD standard mounting flanges, drive shaft splines, port positions, and mounting dimensions fully consistent with original pumps. During equipment repair and replacement, the pump can be installed directly without modifying couplings, piping, or mounting bases — dramatically reducing downtime. The RE241578 and RE241577 can be cross-referenced for use, with specific selection confirmed by tractor model.

5. Precise Matching with 4045/6068 Engines: The pump’s drive interface and mounting position are specifically designed for 4045 and 6068 series engines, ensuring precise alignment with the engine PTO or gear drive system for high transmission efficiency and reliable installation.

Application Areas

• John Deere 1054 Tractor: Main hydraulic pump for steering and hitch systems

• John Deere 1204 Tractor: Hydraulic steering and hitch lift system power source

• John Deere 1354 Tractor: Main hydraulic pump drive

• John Deere 1404 Tractor: Steering and implement hydraulic system supply

• John Deere 6603 Tractor: 6-cylinder tractor main hydraulic pump

• John Deere 6403 Tractor (RE241577): Fits 6079–6403, 9201–6403 models

• John Deere 904 Tractor (RE241577): Fits 11513–904 China Edition model

Expert Maintenance Tips

1. Shaft Alignment and Flange Connection: Concentricity deviation between the pump and engine drive shaft must be less than 0.05 mm, with angular deviation less than 0.25°. The RE241578/RE241577 uses JD standard flange mounting. Tighten flange bolts in diagonal sequence for even loading. When replacing the pump, check that the original mounting base locating step is in good condition — repair the base before installing a new pump if worn.

2. Initial Start-Up Filling and Bleeding: Pre-fill the pump with clean ISO VG46 hydraulic oil through the drain port before installation. Start the engine at the lowest speed and observe a steady oil flow from the case drain port free of bubbles. Once bleeding is complete, gradually increase to working pressure. Note that when hydraulic fluid temperature is below 10°C, warm-up operation is recommended to avoid insufficient suction under cold-start high-viscosity conditions.

3. Tandem Pump Port Correspondence Verification: Both the RE241578 and RE241577 are tandem pump groups. Before installation, verify that the front and rear pump group inlet and outlet ports correctly correspond to the system piping. The front pump group typically supplies the main hydraulic system, while the rear pump group supplies the steering system. Incorrect port connection will result in heavy steering or weak lift performance.

4. Rotation Direction Verification: This model is left-hand (counter-clockwise) rotation as viewed from the drive shaft end. Driving it clockwise is strictly prohibited — incorrect drive direction will reverse the suction and pressure sides, causing severe gear and bearing wear within a short period.

5. Fluid Cleanliness and Filter Replacement: Use ISO VG46 anti-wear hydraulic oil with system filtration of 25 μm or finer. Although external gear pumps have strong contamination tolerance, maintaining fluid cleanliness remains critical for extended pump life. Replace filter elements after the first 500 operating hours, then every 1,000 hours or annually thereafter. Regularly inspect the suction strainer for clogging — a blocked suction strainer can cause insufficient suction and cavitation.

6. Case Drain Line Inspection: The case drain line must return directly to the reservoir with backpressure not exceeding 0.5 bar. The drain line inner diameter must be sufficient to ensure unobstructed drainage during cold-start conditions. Regularly inspect the drain line for kinks, bends, or blockages.