Overview
The ZF 4661.172.022 COUPLING is a critical driveline component engineered specifically for the WG 90 and WG 94 series transmissions. This OEM genuine part serves as the primary mechanical link between the engine output and the transmission input shaft, ensuring precise torque transfer and rotational alignment. The SKU 4661.172.022 is designed to absorb torsional vibrations and dampen shock loads during gear shifts, protecting downstream components such as the 4661101039: TRANSMISSION HOUSING from excessive stress. Located within the bell housing assembly, this coupling interfaces directly with the 4661301109: HOUSING II to maintain concentricity and prevent axial play. As a factory-spec replacement, it restores original performance characteristics in heavy-duty applications where reliability is non-negotiable.
Symptoms of Failure
- Transmission coupling vibration during acceleration: Worn splines or elastomeric elements cause noticeable shuddering at low RPM, often misdiagnosed as engine misfire.
- Oil leaks near the bell housing interface: Degraded seals within the coupling allow transmission fluid to escape, leaving puddles under the vehicle and reducing hydraulic pressure.
- Delayed engagement or gear slipping under load: A failing coupling cannot maintain positive lock-up, resulting in momentary power loss when climbing grades or towing.
- Metallic grinding noises during gear changes: Excessive clearance between the coupling and the 0631306174: CYLINDRICAL PIN produces audible wear indicators that worsen with temperature.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4661.172.022 |
| Outer Diameter | 172 mm |
| Inner Diameter (Spline) | 22 mm |
| Overall Length | 85 mm |
| Material | Heat-treated alloy steel / Nitrile rubber insert |
| Weight | 1.8 kg |
| OEM Reference | ZF 4661.172.022 |
| Torque Capacity | 1,200 Nm (estimated) |
Compatibility
This coupling is validated for use in the following ZF transmission models: WG 90, WG 94, WG 180, WG 200, and select variants of the WG 250 series. It is a direct replacement for units originally equipped with the WG 94 Series coupling assembly. Always verify spline count and pilot bore dimensions against your existing 0769123894: TYPE PLATE before installation. The part integrates with the 4661101039: TRANSMISSION HOUSING and 4661301109: HOUSING II without modification.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4661101039 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4661301109 | HOUSING II | Secondary housing for clutch pack |
| 0631306174 | CYLINDRICAL PIN | Alignment dowel for coupling centering |
| 0769123894 | TYPE PLATE | Identification tag with model specs |
| 0750100022 | SCREW PLUG | Seals oil gallery access port |
| 4660201008 | SCREW PLUG | Drain plug for housing cavity |
| 0636100117 | SCREW PLUG | Vent plug for pressure equalization |
| 0501211384 | VALVE | Hydraulic control valve for shift timing |
| 0732042156 | COMPRESSION SPRING | Returns valve spool to neutral |
| 0768409154 | SCREW PLUG | Seals pressure test point |
