Overview
The ZF 4657.120.004 PRESSURE REGULATOR is a precision hydraulic control component engineered specifically for the WG 210 Series transmission family. This OEM genuine part governs the modulation of hydraulic pressure within the valve body, ensuring consistent clutch and brake application during gear shifts. By maintaining precise oil pressure, the 4657.120.004 directly influences shift quality and torque converter lockup behavior. This pressure regulator sits within the main control unit of the transmission, interfacing with the 4657101047: TRANSMISSION HOUSING and the 4657201027: HOUS.FRONT SECT to regulate fluid flow paths.
Symptoms of Failure
- Erratic shift timing and gear slipping under load — When the 4657.120.004 pressure regulator wears, hydraulic pressure fluctuates, causing delayed or harsh shifts, particularly when towing or climbing grades.
- Oil leaks around the valve body area — A degraded regulator seal or bore wear can allow transmission fluid to escape, leaving puddles under the vehicle and reducing overall system pressure.
- Torque converter shudder or lockup failure — Inconsistent pressure regulation prevents proper converter clutch engagement, resulting in vibration during highway cruising or complete loss of lockup function.
- Overheating transmission fluid — Slipping clutches caused by improper pressure generate excess heat, accelerating fluid degradation and potentially damaging the 4657201020: HOUSING REAR PART.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4657.120.004 |
| OEM Reference | ZF 4657.120.004 |
| Material | Hardened steel with corrosion-resistant coating |
| Weight | 0.35 kg (0.77 lbs) |
| Overall Length | 85 mm |
| Outer Diameter | 28 mm |
| Operating Pressure Range | 5–22 bar |
| Seal Type | PTFE lip seal |
Compatibility
This pressure regulator is a direct-fit component for the ZF WG 210 Series transmissions. Based on its design and hydraulic characteristics, it is also compatible with the following ZF models: WG180, WG200, WG211, and WG220. The part is commonly used in municipal trucks, refuse vehicles, and medium-duty construction equipment. Always verify fitment by cross-referencing your transmission serial number with the 0631306792: CYLINDRICAL PIN alignment specifications.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4657101047 | TRANSMISSION HOUSING | Main structural casing for gear and valve body assembly |
| 4657201027 | HOUS.FRONT SECT | Front section housing torque converter and pump |
| 4657201020 | HOUSING REAR PART | Rear housing supporting output shaft and PTO mount |
| 0631306792 | CYLINDRICAL PIN | Alignment dowel for housing mating surfaces |
| 0636100801 | CAP SCREW | Fastener for valve body cover plate |
| 4656301148 | FIXING PLATE | Retainer for pressure regulator spring |
| 4657301032 | SCREEN SHEET | Fine mesh filter for valve body oil gallery |
| 4657301033 | SCREEN SHEET | Coarse mesh pre-filter for main pressure line |
| 0636100803 | CAP SCREW | Bolt for securing oil feed housing |
| 0750301003 | OIL FEED.HOUSG. | Pressurized oil supply manifold to regulator |
Frequently Asked Questions
Q: How do I know if my ZF WG210 needs a new 4657.120.004 pressure regulator?
A: Perform a stall test and monitor line pressure with a gauge. If pressure drops below 12 bar at idle or fluctuates more than 2 bar during shifts, the regulator is likely worn.
Q: Can I install this part without removing the transmission from the vehicle?
A: Yes, in most applications the valve body is accessible after draining the fluid and dropping the transmission pan. However, you must replace the 0636100801: CAP SCREW gaskets during reassembly.
Q: Is this pressure regulator interchangeable with the WG180 series?
A: The 4657.120.004 shares the same bore diameter and spring rate as the WG180 regulator, but we recommend verifying the 4656301148: FIXING PLATE orientation differs between series.
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Phone: +86 158 2286 3467 |
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