Overview
The ZF 4660.172.002 COUPLING is a critical torque-transfer component engineered for the WG 92 and WG 98 transmission series. Positioned between the engine flywheel and the transmission input shaft, this OEM genuine part ensures smooth power delivery and dampens torsional vibrations during gear shifts. The SKU 4660.172.002 is precision-machined to factory tolerances, directly interfacing with the 4660101017: TRANSMISSION HOUSING and the 4660301054: HOUSING II to maintain concentric alignment. Without this coupling, the transmission cannot properly engage the driveline, making it a non-negotiable element for any rebuild or overhaul of the WG 98 assembly.
Symptoms of Failure
- Torque converter shudder during acceleration: A worn 4660.172.002 coupling causes noticeable vibration between 1,200 and 1,800 RPM, often misdiagnosed as a failing torque converter.
- Metallic clicking from the bell housing: Loose or fatigued coupling teeth produce a distinct “click-click” sound when shifting from Neutral to Drive, indicating imminent spline wear.
- Fluid contamination with metallic debris: As the coupling degrades, fine steel particles enter the transmission fluid, visible during routine drain intervals. This symptom often accompanies failure of the 0631306174: CYLINDRICAL PIN that secures the coupling hub.
- Intermittent loss of forward motion: In severe cases, the coupling slips entirely, causing the vehicle to hesitate or fail to move despite engine RPM increase. Check the 0769123894: TYPE PLATE for correct part identification before replacement.
Technical Specifications
| Parameter | Value |
|---|---|
| OEM Part Number | 4660.172.002 |
| Outer Diameter | 172 mm |
| Inner Spline Diameter | 38 mm |
| Material | Case-hardened steel (20MnCr5) |
| Weight | 2.4 kg |
| Torque Capacity | 1,200 Nm (peak) |
| OEM Reference | ZF 4660.172.002 |
Compatibility
This coupling is specifically validated for the ZF WG 98 series, including the WG180, WG200, and WG210 variants. It also retrofits to earlier WG 92 models (WG120, WG150) when used with the updated TRANSMISSION HOUSING. Always verify the spline count (typically 24 teeth) against your existing coupling. The part is not compatible with Ecomat or Ecolife series without adapter plates.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4660101017 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4660301054 | HOUSING II | Rear housing section for output shaft |
| 0631306174 | CYLINDRICAL PIN | Alignment pin for coupling hub |
| 0769123894 | TYPE PLATE | Identification plate for transmission model |
| 0750100022 | SCREW PLUG | Seals fluid drain/fill ports |
| 4660221029 | SUCTION TUBE | Oil pickup from pan to pump |
| 0634100317 | O-RING | Seals housing joint surfaces |
| 0636103273 | CAP SCREW | Fastener for housing bolts |
| 0634306311 | O-RING | Seals suction tube connection |
| 4660321029 | FIXING PLATE | Retains coupling on input shaft |
