Overview
The ZF 4166.337.184 PUMP FLANGE is a precision-machined component engineered specifically for the WG 65 series transmission family. This OEM genuine part serves as the critical interface between the hydraulic pump and the transmission housing, ensuring proper alignment and oil flow for clutch actuation and lubrication circuits. The SKU 4166.337.184 mounts directly to the TRANSMISSION HOUSING, providing a sealed connection that maintains system pressure. Without this flange, the pump cannot deliver the hydraulic force required for gear engagement, making it essential for driveline reliability in heavy-duty applications.
Symptoms of Failure
- Hydraulic oil seepage around pump mounting area – When the flange face warps or the sealing surface degrades, pressurized transmission fluid escapes, leaving visible puddles under the vehicle after extended operation.
- Erratic gear engagement or delayed shifting – A worn pump flange reduces hydraulic pressure consistency, causing the transmission to hesitate or slip when shifting between forward and reverse gears.
- Whining noise from the pump cavity – Misalignment from a damaged flange creates abnormal pump bearing loads, producing a high-pitched whine that increases with engine RPM.
- Overheating transmission fluid – Insufficient pump flow due to flange leakage or misalignment leads to inadequate cooling circulation, triggering thermal warnings on the dashboard.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | 4166.337.184 |
| Material | High-grade cast iron with corrosion-resistant coating |
| Overall Diameter | 185 mm |
| Bolt Hole Pattern | 6x M12 on 160 mm PCD |
| Weight | 2.4 kg |
| OEM Reference | ZF 4166.337.184 |
| Sealing Method | Integrated O-ring groove (uses O-RING) |
| Fastener Torque | 85 Nm (uses HEXAGON SCREW) |
Compatibility
This pump flange is designed for the ZF WG 65 series, but it also fits select models in the WG180 and WG200 families due to shared pump mounting interfaces. It is commonly found in WG65-6, WG65-7, and WG65-8 transmissions used in municipal trucks, fire apparatus, and construction equipment. For proper installation, always pair this flange with a new O-RING and secure it using the correct HEXAGON SCREW torque specifications. The flange interfaces directly with the OUTPUT FLANGE assembly and the OUTPUT shaft, ensuring concentric alignment during pump operation.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4616105402 | OUTPUT | Transfers rotational power from transmission to driveshaft |
| 4005303005 | OUTPUT FLANGE | Connects output shaft to universal joint |
| 4616101119 | TRANSMISSION HOUSING | Main structural casing enclosing gear sets |
| 0636011038 | HEXAGON SCREW | Secures pump flange to housing |
| 0636011118 | HEXAGON SCREW | Fastens output flange to shaft |
| 0636016015 | HEXAGON SCREW | Mounts transmission housing components |
| 0631306085 | CYLINDRICAL PIN | Aligns flange to housing during assembly |
| 0634313118 | O-RING | Creates hydraulic seal between flange and housing |
| 0636304019 | SCREW PLUG | Seals oil passages in transmission case |
| 0634801152 | SEALING RING | Prevents fluid leaks at threaded connections |
