Overview
The ZF 4657.173.021 COUPLING is a critical torque-transfer component engineered for the WG 190 and WG 210 series transmissions. This OEM genuine part sits directly between the engine flywheel and the transmission input shaft, acting as a vibration-dampening interface that ensures smooth power delivery under heavy loads. Designed to withstand high torsional stress, the coupling (SKU: 4657.173.021) maintains precise alignment within the drivetrain assembly, reducing wear on adjacent components such as the TRANSMISSION HOUSING and the HOUS.FRONT SECT. Without this coupling, the transmission cannot properly engage with the engine, making it a non-negotiable element for operational reliability.
Symptoms of Failure
- Torque fluctuation under acceleration: When the coupling wears, operators often report “ZF transmission shudder on takeoff” or “WG 210 jerky engagement” due to degraded dampening material.
- Metallic rattling at idle: A loose or fatigued coupling produces a distinct “ZF WG 190 rattling noise in neutral” as the metal hub loses its press-fit tolerance.
- Oil seepage near the bell housing: Cracks in the coupling body can cause “ZF transmission oil leak at flywheel housing” symptoms, often mistaken for a failing seal.
- Increased driveline backlash: Operators may notice “WG 200 transmission clunking when shifting” as the coupling’s splines wear, creating excessive play.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4657.173.021 |
| Outer Diameter | 210 mm (estimated) |
| Inner Diameter (Spline) | 45 mm |
| Overall Length | 85 mm |
| Material | High-tensile steel with rubber dampening insert |
| Weight | 3.2 kg |
| OEM Reference | ZF 4657.173.021 |
| Torque Capacity | 1,200 Nm (max) |
Compatibility
This coupling is specifically designed for ZF WG series transmissions, including the WG 180, WG 190, WG 200, WG 210, and WG 230 models. It is a direct replacement for the original coupling found in the WG 210 Series and WG 230 Series categories. For proper installation, ensure the HOUSING REAR PART is free of debris, and use the CYLINDRICAL PIN for alignment during reassembly. Always verify your transmission’s serial number against the WG series compatibility chart before ordering.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4657101033 | TRANSMISSION HOUSING | Encloses and supports internal gear sets |
| 4657201027 | HOUS.FRONT SECT | Front section of the transmission casing |
| 4657201012 | HOUSING REAR PART | Rear section of the transmission casing |
| 0631306792 | CYLINDRICAL PIN | Alignment pin for housing assembly |
| 0636100801 | CAP SCREW | Fastener for coupling retention |
| 4656301148 | FIXING PLATE | Secures coupling to input shaft |
| 4657301032 | SCREEN SHEET | Fine mesh filter for oil circuit |
| 4657301033 | SCREEN SHEET | Coarse mesh filter for oil circuit |
| 0636100803 | CAP SCREW | Fastener for housing sections |
| 4681301040 | OIL FEED.HOUSG. | Distributes lubrication to coupling area |
Frequently Asked Questions
Q: Can the ZF 4657.173.021 coupling be used in a WG 180 transmission?
A: Yes, this coupling is compatible with WG 180, WG 190, WG 200, WG 210, and WG 230 models, provided the spline count and pilot bore match your specific unit.
Q: How do I know if my coupling needs replacement without removing the transmission?
A: Listen for a distinct “clunk” when shifting from Park to Drive, or check for radial play by rotating the driveshaft with the engine off. Excessive movement indicates wear.
Q: Is the rubber dampening insert replaceable separately?
A: No, the 4657.173.021 is a one-piece assembly. The rubber insert is vulcanized to the steel hub and cannot be serviced individually.
📞 Need this part? Contact our ZF specialists:
Email: info@partszf.com |
Phone: +86 158 2286 3467 |
Request a Quote →
