Overview
The ZF 4657.171.050 COUPLING is a critical driveline component engineered specifically for the WG 190 and WG 210 transmission series. This OEM genuine part serves as the primary torque-transfer interface between the engine output and the transmission input shaft, ensuring smooth power delivery under heavy-duty industrial loads. The SKU 4657.171.050 is precision-machined to maintain concentric alignment, reducing vibration and preventing premature wear on adjacent assemblies. It sits directly within the bell housing area, connecting directly to the TRANSMISSION HOUSING to form a sealed, rigid coupling unit.
Symptoms of Failure
- Torque converter shudder at low RPM: A pronounced vibration during acceleration from a stop, often misdiagnosed as a slipping clutch, indicates the coupling has lost its damping capacity.
- Transmission fluid contamination with metallic debris: When the coupling splines or friction surfaces wear, fine metal particles appear in the oil pan, visible during routine fluid changes.
- Audible clunking during gear engagement: A distinct metallic “clunk” when shifting from Neutral to Drive or Reverse signals excessive backlash in the coupling hub.
- Oil weeping from the bell housing inspection cover: Worn seals on the coupling hub allow transmission fluid to escape, leaving visible drips under the vehicle after extended operation.
Technical Specifications
| Parameter | Specification |
|---|---|
| OEM Part Number | 4657.171.050 |
| Outer Diameter | 210 mm |
| Inner Spline Diameter | 38 mm |
| Overall Length | 95 mm |
| Material | Forged alloy steel with nitrided surface |
| Weight | 2.8 kg (6.2 lbs) |
| Torque Capacity | 1,200 Nm (885 lb-ft) |
| Operating Temperature Range | -40°C to +120°C |
Compatibility
This coupling is designed for the ZF WG 210 Series transmissions, including the WG 210, WG 211, and WG 212 variants. It also retrofits to earlier WG 190 models with the same bell housing pattern. The part interfaces directly with the HOUS.FRONT SECT and the HOUSING REAR PART to complete the main casing assembly. For full rebuilds, the HOUSING REAR SECTION must also be inspected for wear at the coupling seat.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4657101078 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4657201166 | HOUS.FRONT SECT | Front section enclosing pump and coupling |
| 4657201168 | HOUSING REAR PART | Rear housing supporting output shaft |
| 4657298101 | HOUSING REAR SECTION | Extended rear section for PTO mounting |
| 0631306816 | CYLINDRICAL PIN | Alignment pin for housing doweling |
| 0636100801 | CAP SCREW | M10 fastener for housing bolts |
| 4656301148 | FIXING PLATE | Retains coupling to input shaft |
| 4657301032 | SCREEN SHEET | Fine mesh filter for oil circuit |
| 4657301033 | SCREEN SHEET | Coarse mesh pre-filter |
| 0636100803 | CAP SCREW | M12 fastener for coupling flange |
Frequently Asked Questions
Q: Can I reuse the old coupling bolts when installing the 4657.171.050?
A: No. ZF specifies that all fasteners, including the CAP SCREW (M12), must be replaced with new OEM parts to ensure proper torque retention and prevent loosening under vibration.
Q: How do I know if my WG 210 needs this coupling or just a new seal?
A: Inspect the coupling hub for visible spline wear or scoring. If the splines appear sharp or the hub has more than 0.5 mm of radial play, replace the coupling. A simple seal leak can be fixed without replacing the coupling if the hub surface is smooth.
Q: Is the 4657.171.050 compatible with the WG 180 transmission?
A: No. The WG 180 uses a smaller 190 mm coupling. This part is specifically designed for the WG 190 and WG 210 series with a 210 mm outer diameter. Always verify your transmission model before ordering.
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Email: info@partszf.com |
Phone: +86 158 2286 3467 |
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