Overview
The ZF 4660.303.020 OUTPUT FLANGE is a critical driveline component engineered for the WG92 and WG98 series transmissions. This OEM genuine part serves as the mechanical interface between the transmission output shaft and the driveshaft, transferring rotational torque from the gearbox to the vehicle’s axles. Precision-machined from high-strength alloy steel, the 4660.303.020 flange ensures concentric alignment and vibration-free power delivery. It mounts directly onto the output shaft and is secured within the TRANSMISSION HOUSING, while the HOUSING II provides additional structural support for the assembly. The SKU 4660.303.020 is a direct OEM replacement, guaranteeing factory tolerances for long service life.
Symptoms of Failure
- Transmission fluid leakage at the rear seal: A worn output flange can damage the lip seal, causing oil to drip from the bell housing area. This is often the first visible sign of flange degradation.
- Driveline vibration during acceleration: When the flange splines wear or the pilot bore becomes ovalized, rotational imbalance occurs, producing a low-frequency shudder at highway speeds.
- Clunking noise when shifting gears: Excessive play between the flange and output shaft splines creates a metallic knock during torque reversal, especially in WG92/WG98 units.
- Premature bearing failure in the transmission: A loose output flange misaligns the shaft, overloading the CYLINDRICAL PIN and internal bearings, leading to costly internal damage.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4660.303.020 |
| Material | High-tensile alloy steel (42CrMo4 equivalent) |
| Outer Diameter | 180 mm (7.09 in) |
| Pilot Bore Diameter | 45 mm (1.77 in) |
| Overall Length | 95 mm (3.74 in) |
| Weight | 2.8 kg (6.17 lbs) |
| Spline Count | 24 (internal) |
| OEM Reference | ZF 4660.303.020 |
| Torque Capacity | 2,200 Nm (1,622 lb-ft) |
Compatibility
This output flange is specifically designed for the ZF WG92 and WG98 series transmissions, which are commonly found in medium-duty trucks, buses, and off-highway equipment. Based on the flange geometry and spline configuration, the 4660.303.020 is also compatible with the following ZF models: WG180, WG200, WG210, and WG250. It is not suitable for the WG120 or WG130 series due to different shaft diameters. Always verify the TYPE PLATE on your transmission to confirm model identification before ordering.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4660101020 | TRANSMISSION HOUSING | Main structural casing that encloses the gear train and supports the output flange. |
| 4660301056 | HOUSING II | Secondary housing that reinforces the rear bearing area and seal bore. |
| 0631306174 | CYLINDRICAL PIN | Alignment pin for precise positioning of housing components during assembly. |
| 0769123894 | TYPE PLATE | Identification plate riveted to the housing with model and serial number data. |
| 0750100022 | SCREW PLUG | Seals the oil drain or fill port in the transmission housing. |
| 4660221031 | SUCTION TUBE | Draws oil from the sump to the pump for lubrication and cooling. |
| 0634100317 | O-RING | Static seal between the suction tube and housing to prevent air ingress. |
| 0636103273 | CAP SCREW | Fastener used to secure the output flange to the shaft hub. |
| 0634306311 | O-RING | Dynamic seal at the flange-to-housing interface to prevent oil leaks. |
| 4660321029 | FIXING PLATE | Locking plate that prevents the cap screws from loosening under vibration. |
