Overview
The ZF 4644.354.010 PUMP FLANGE is a precision-machined component designed for the WG 201 series of ZF transmissions. This OEM genuine part serves as the critical interface between the hydraulic pump and the transmission housing, ensuring proper alignment and sealing for optimal oil flow. The SKU 4644.354.010 is specifically engineered to withstand high torque loads and thermal expansion during operation. It mounts directly to the 4644101160: TRANSMISSION HOUSING and works in conjunction with the 4644301323: TRANSMISSION HOUSING to create a sealed pump drive assembly. Without this flange, the hydraulic pump cannot maintain pressure, leading to immediate transmission performance degradation.
Symptoms of Failure
- Hydraulic oil seepage around the pump mounting area – When the flange surface warps or the sealing face degrades, oil leaks become visible at the pump-to-housing joint, often mistaken for a pump seal failure.
- Erratic gear engagement under load – A worn flange causes pump misalignment, resulting in inconsistent hydraulic pressure that manifests as delayed or slipping shifts during acceleration.
- Unusual whining noise from the transmission pump – As the flange loses its concentricity, the pump shaft experiences lateral stress, producing a high-pitched whine that intensifies with RPM.
- Visible fretting corrosion on the flange mating surface – Vibration-induced micro-movement between the flange and housing creates reddish-brown wear marks, indicating imminent failure of the 4644301189: THREADED BUSH that secures the assembly.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4644.354.010 |
| Material | High-strength cast iron (GGG-40) |
| Outer Diameter | 185 mm |
| Inner Bore Diameter | 65 mm |
| Flange Thickness | 22 mm |
| Bolt Hole Pattern | 6x M12 on 150 mm PCD |
| Weight | 1.85 kg |
| OEM Reference | ZF 4644.354.010 |
| Surface Finish | Ra 0.8 µm (sealing face) |
Compatibility
This pump flange is primarily designed for the ZF WG 201 series transmissions, including models WG201, WG202, and WG203. It also fits select WG180 and WG200 variants that share the same pump mounting interface. The flange is compatible with transmissions using the 4475280043: SCREW PLUG for oil gallery sealing. Always verify the bolt pattern and pilot diameter against your specific transmission model before installation. For WG200 series units, cross-reference with the 4644301161: COVER PLATE to ensure correct pump alignment.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101160 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4644301323 | TRANSMISSION HOUSING | Secondary housing section for pump mount |
| 4644301189 | THREADED BUSH | Reinforced insert for flange bolts |
| 4475280043 | SCREW PLUG | Seals oil passages in housing |
| 0634306198 | O-RING | Provides static seal between flange and pump |
| 0730365067 | TYPE PLATE | Identification tag for transmission model |
| 4644301161 | COVER PLATE | Protects pump drive gear from debris |
| 0636100621 | HEXAGON SCREW | Fastens flange to housing |
| 0631610020 | SET SCREW | Locks flange alignment during assembly |
| 0501218540 | BREATHER | Equalizes internal transmission pressure |
