Overview
The ZF 4644.303.207 OUTPUT FLANGE is a critical driveline component engineered specifically for the WG 201 series transmission. 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. Machined from high-strength forged steel, the flange features precision splines that lock onto the output shaft, while its bolt pattern ensures a vibration-free connection to the universal joint. As an original ZF component, SKU 4644.303.207 guarantees exact fitment and metallurgical integrity, eliminating the risk of premature wear associated with aftermarket alternatives. This flange is mounted directly behind the 4644101160: TRANSMISSION HOUSING and works in concert with the 4644301189: THREADED BUSH to maintain proper shaft alignment.
Symptoms of Failure
- Transmission fluid seepage at the output shaft seal — A worn flange surface or cracked spline hub allows oil to bypass the seal, leaving drips under the bell housing. This is the most common indicator that the 4644.303.207 requires replacement.
- Driveline vibration during acceleration — When the flange’s pilot bore becomes distorted or its bolt holes elongate, the driveshaft runs out of true, causing rhythmic shaking that intensifies with speed.
- Clunking noise when shifting between drive and reverse — Excessive backlash in the spline engagement creates a metallic knock as torque direction changes, signaling that the flange teeth are worn beyond tolerance.
- Visible corrosion or pitting on the flange face — Rust formation around the seal contact area compromises the sealing surface, leading to progressive oil loss and potential contamination of the 4644301323: TRANSMISSION HOUSING.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4644.303.207 |
| OEM Reference | ZF 4644 303 207 |
| Material | Forged steel, induction-hardened spline |
| Overall Diameter | 165 mm (6.50 in) |
| Overall Length | 95 mm (3.74 in) |
| Spline Count | 24 internal splines |
| Bolt Hole Pattern | 8 holes, 14 mm diameter on 130 mm PCD |
| Weight | 2.8 kg (6.2 lbs) |
| Seal Surface Hardness | HRC 45-50 |
| Max Torque Capacity | 2,200 Nm |
Compatibility
This output flange is designed for the ZF WG 201 series transmissions, which are widely used in medium-duty trucks, buses, and construction equipment. It is directly compatible with the following ZF models: WG180, WG200, WG201, WG210, and WG220. The flange also fits select variants of the Ecomat 4HP and 6HP series where the output shaft spline configuration matches. Always verify the spline count and pilot bore diameter against your existing flange before installation. When replacing this part, it is recommended to also install a new 0634306198: O-RING on the output shaft and inspect the 4475280043: SCREW PLUG for the oil drain port.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101160 | TRANSMISSION HOUSING | Main structural casing that encloses the gear train |
| 4644301323 | TRANSMISSION HOUSING | Alternative housing variant for WG201 series |
| 4644301189 | THREADED BUSH | Provides threaded mounting point for flange bolts |
| 4475280043 | SCREW PLUG | Seals the oil fill or drain port in the housing |
| 0634306198 | O-RING | Creates a fluid-tight seal between flange and shaft |
| 0730365067 | TYPE PLATE | Identification plate riveted to the transmission housing |
| 4644301161 | COVER PLATE | Protects the rear bearing area from debris |
| 0636100621 | HEXAGON SCREW | Fastens the cover plate to the housing |
| 0631610020 | SET SCREW | Locks the flange to the output shaft |
| 0501218540 | BREATHER | Equalizes internal pressure in the transmission |
