Overview
The ZF 4656.185.073 ACCESSORIES for WG171 is a precision-engineered component designed to support the internal lubrication and hydraulic circuits within the WG 171 Series transmission. This genuine OEM part functions as a critical interface element, ensuring proper fluid routing and pressure stability during gear shifts. The SKU 4656.185.073 is manufactured to ZF’s exacting tolerances, making it a direct replacement for worn units in heavy-duty commercial vehicle transmissions. It sits within the valve body assembly area, where it interacts with the TRANSMISSION HOUSING and the HOUS.FRONT SECT to maintain correct oil gallery alignment.
Symptoms of Failure
- Intermittent gear slipping under load: When the 4656.185.073 accessory wears, hydraulic pressure drops, causing the transmission to slip during uphill climbs or heavy towing.
- External oil seepage near the valve body: A degraded seal or cracked accessory body leads to visible fluid leaks around the transmission pan, often mistaken for a pan gasket failure.
- Delayed engagement from Neutral to Drive: Worn internal passages restrict oil flow, resulting in a 2–3 second lag before the transmission engages.
- Erratic shift timing: The control module receives inconsistent pressure signals, causing harsh or unpredictable shifts between gears.
Technical Specifications
| Specification | Value |
|---|---|
| OEM Part Number | 4656.185.073 |
| Material | Die-cast aluminum alloy with nitrile seals |
| Weight | 0.42 kg (0.93 lbs) |
| Overall Length | 85 mm |
| Width | 42 mm |
| Height | 28 mm |
| Operating Temperature Range | -40°C to +120°C |
| OEM Reference | ZF 4656.185.073 |
Compatibility
This genuine ZF accessory is engineered primarily for the WG 171 Series transmission family. Based on its design and hydraulic routing, it also fits the WG 180 and WG 200 series models produced between 2005 and 2020. The part is not compatible with the older WG 150 series without modification. For proper installation, ensure the SCREEN SHEET and TUBE are inspected for debris accumulation before fitting the new accessory.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4656101028 | TRANSMISSION HOUSING | Encloses gear sets and supports bearing alignment |
| 4656301066 | HOUS.FRONT SECT | Front section housing for pump and converter |
| 4656201015 | SCREEN SHEET | Filters debris from hydraulic fluid |
| 4656301037 | TUBE | Routes oil between valve body and cooler |
| 0634313514 | O-RING | Seals fluid connections to prevent leaks |
| 0636100803 | CAP SCREW | Secures housing sections together |
| 4656301042 | HOUSING REAR PART | Rear section housing for output shaft |
| 0631306816 | CYLINDRICAL PIN | Aligns components during assembly |
| 0636100801 | CAP SCREW | Fastens valve body to housing |
| 0636100160 | CAP SCREW | Mounts accessory bracket to transmission |
Frequently Asked Questions
Q: Can the 4656.185.073 accessory be reused after a transmission rebuild?
A: No. ZF recommends replacing this accessory with a new OEM unit during any major overhaul, as the internal sealing surfaces degrade over time and cannot be reliably reconditioned.
Q: How do I verify that this part fits my WG 171 transmission?
A: Check the transmission data plate for the model code. If it begins with “WG171” and the serial number falls between 2005 and 2020, the 4656.185.073 is the correct replacement. Always inspect the SCREEN SHEET for damage before installation.
Q: What torque specification is required for the mounting bolts?
A: Use 12 Nm (9 ft-lbs) for the cap screws securing this accessory. Over-torquing can crack the aluminum housing. Refer to the CAP SCREW specifications for exact fastener requirements.
📞 Need this part? Contact our ZF specialists:
Email: info@partszf.com |
Phone: +86 158 2286 3467 |
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