Overview
The ZF 4166.339.227 STATOR is a precision-engineered hydraulic component designed exclusively for the WG 65 series of automatic transmissions. Positioned within the torque converter assembly, this OEM genuine part redirects fluid flow to multiply torque during initial acceleration and lock-up phases. The stator, identified by SKU 4166.339.227, works in concert with the turbine and impeller to optimize power transfer from the engine to the drivetrain. When paired with a robust OUTPUT and a secure OUTPUT FLANGE, this stator ensures consistent hydraulic pressure regulation across all operating ranges.
Symptoms of Failure
- Delayed engagement or gear slipping: A worn stator vane set can cause insufficient torque multiplication, leading to hesitation when shifting from neutral to drive or reverse.
- Overheating transmission fluid: If the stator fails to redirect oil correctly, the converter generates excessive heat, often indicated by a burnt smell or dashboard temperature warnings.
- Loss of power under load: Operators may notice reduced acceleration on inclines or when towing, as the stator cannot maintain proper fluid coupling.
- Unusual whining or grinding noises: Mechanical wear on the stator hub or bearings produces audible sounds from the bell housing area during gear changes.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4166.339.227 |
| Material | Aluminum alloy with hardened steel hub |
| Weight | 2.8 kg (6.2 lbs) |
| Outer Diameter | 245 mm |
| Hub Bore Diameter | 35 mm |
| Vane Count | 27 |
| OEM Reference | ZF 4166.339.227 |
Compatibility
This stator is engineered for the ZF WG65 transmission family, which includes models such as WG65, WG80, WG120, WG150, WG180, and WG200. It is a direct replacement for units found in municipal buses, construction loaders, and medium-duty trucks. For proper installation, ensure the TRANSMISSION HOUSING is free of debris and that all fasteners, including the HEXAGON SCREW, are torqued to factory specifications. The stator interfaces directly with the pump drive hub and requires no modification for retrofit into earlier WG series builds.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4616105402 | OUTPUT | Transfers torque from transmission to driveshaft |
| 4005303005 | OUTPUT FLANGE | Connects output shaft to universal joint |
| 4616101119 | TRANSMISSION HOUSING | Encloses gear train and hydraulic components |
| 0636011038 | HEXAGON SCREW | Secures stator to pump housing |
| 0636011118 | HEXAGON SCREW | Fastens output flange to shaft |
| 0636016015 | HEXAGON SCREW | Mounts transmission housing to bell housing |
| 0631306085 | CYLINDRICAL PIN | Aligns stator and pump assembly |
| 0634313118 | O-RING | Seals stator hub to prevent fluid bypass |
| 0636304019 | SCREW PLUG | Closes oil passages in housing |
| 0634801152 | SEALING RING | Prevents external oil leaks at stator shaft |
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