Overview
The ZF 0501.327.426 PRESSURE REGULATOR is a critical hydraulic control component engineered to maintain precise oil pressure within ZF powershift transmissions. Positioned within the valve body assembly, this OEM genuine part modulates fluid flow to ensure consistent clutch engagement and smooth gear shifts. The SKU 0501.327.426 is specifically designed to withstand high thermal loads and continuous operation in construction machinery, such as wheel loaders and graders. When functioning correctly, it prevents pressure spikes that could damage internal seals and rotating assemblies like the 2093109018: DIFFERENTIAL.
Symptoms of Failure
When the 0501.327.426 pressure regulator begins to wear, operators may notice several distinct performance issues. Delayed or harsh shifting is a primary indicator, as inconsistent hydraulic pressure prevents smooth clutch pack engagement. Another common symptom is transmission overheating, caused by the regulator failing to maintain proper oil flow through the cooler circuit. Intermittent gear slippage under load often occurs when the valve sticks open or closed, leading to pressure loss. Finally, erratic pressure gauge readings or visible oil seepage around the valve body suggest the regulator’s internal spring or spool has fatigued.
Technical Specifications
| Specification | Detail |
|---|---|
| Part Number | 0501.327.426 |
| Material | Hardened Steel / Aluminum Alloy |
| Weight | 0.45 kg (1.0 lb) |
| Dimensions (L x W x H) | 85 mm x 40 mm x 35 mm |
| OEM Reference | ZF 0501.327.426 |
| Operating Pressure Range | 10–25 bar (145–362 psi) |
| Seal Type | Nitrile Rubber O-Ring |
Compatibility
This pressure regulator is engineered for ZF powershift transmissions commonly found in heavy construction equipment. It is a direct fit for the ZF WG180 and ZF WG200 series, as well as the ZF 4WG-200 and ZF 4WG-310 models. These transmissions are installed in brands such as Case, New Holland, Liebherr, and Volvo. For optimal performance, always pair this regulator with a properly torqued 0631329088: SPRING PIN and inspect the 5838300811: THRUST WASHER for wear during installation.
Related Components
During a full transmission rebuild, several companion parts should be replaced simultaneously to ensure system integrity. The 0750117075: TAPER ROLLER BEARING supports axial loads on the output shaft, while the 2093209023: DIFFERENTIAL distributes torque to the wheels. The 5838300626: DIFFERENTIAL HOUSING encloses the gear set and must be free of cracks. Additional parts like the 5838300721: AXLE BEVEL GEAR and 5838300633: AXLE are also commonly serviced together.
| Part Number | Name | Function |
|---|---|---|
| 2093109018 | DIFFERENTIAL | Distributes engine torque to drive axles |
| 0750117075 | TAPER ROLLER BEARING | Supports radial and axial shaft loads |
| 2093209023 | DIFFERENTIAL | Allows wheel speed variation during turns |
| 5838300626 | DIFFERENTIAL HOUSING | Encloses and protects differential gears |
| 0631329088 | SPRING PIN | Secures valve components in the bore |
| 5838300811 | THRUST WASHER | Reduces axial friction between gears |
| 5838300721 | AXLE BEVEL GEAR | Transfers power to the wheel hub |
| 5838300633 | AXLE | Rotates to drive the final drive assembly |
| 5838300753 | THRUST WASHER | Prevents metal-to-metal contact in gear sets |
| 5838300818 | THRUST WASHER | Provides axial clearance control |
Frequently Asked Questions
Q: How do I know if the 0501.327.426 pressure regulator is failing?
A: Watch for delayed gear engagement, transmission shuddering during acceleration, or fluctuating pressure on your dash gauge. A sticking spool often causes intermittent clutch slip.
Q: Can I install this regulator without replacing the differential components?
A: Yes, but we recommend inspecting the 2093109018: DIFFERENTIAL and 5838300626: DIFFERENTIAL HOUSING for wear, as contaminated oil from a failing regulator can damage these parts over time.
Q: Is this part compatible with ZF WG180 transmissions from 1998?
A: Yes, the 0501.327.426 fits WG180 and WG200 series transmissions manufactured from 1995 onward. Always verify your valve body casting number for exact match.
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Phone: +86 158 2286 3467 |
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