Overview
The ZF 4661.134.004 CONVERTER Powershift Transmission Assembly is a complete, factory-sealed unit designed for the torque converter circuit within ZF’s heavy-duty WG 90 and WG 94 series transmissions. This assembly integrates the converter stator, impeller, and turbine components into a single, pre-assembled module, ensuring precise hydraulic coupling and torque multiplication during low-speed operation. The SKU 4661.134.004 is a direct replacement for worn or failed converter assemblies, restoring full power transfer efficiency in wheel loaders, forklifts, and industrial tractors. It sits between the engine flywheel and the transmission input shaft, directly interfacing with the TRANSMISSION HOUSING and the HOUSING II to maintain proper alignment and fluid sealing.
Symptoms of Failure
- Torque converter shudder or vibration during acceleration – Worn internal clutches or damaged vanes in the 4661.134.004 assembly cause uneven hydraulic pressure, leading to noticeable shaking when moving from a stop.
- Transmission overheating and fluid discoloration – A failing converter generates excessive heat due to internal slippage, often turning transmission fluid dark brown or burnt-smelling.
- Delayed or harsh engagement when shifting from neutral to drive – Reduced converter lock-up capability results in a lag of 2–3 seconds before power is transmitted, followed by a sudden jolt.
- Audible whining or grinding noise from the bell housing area – Worn bearings or impeller damage inside the converter produce a high-pitched whine that increases with engine RPM.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4661.134.004 |
| Assembly Type | Complete Converter / Torque Converter Unit |
| Overall Diameter | 340 mm (13.4 in) |
| Overall Length | 210 mm (8.3 in) |
| Weight | 18.5 kg (40.8 lbs) |
| Housing Material | Aluminum Alloy (A356-T6) |
| Impeller Material | Steel (SAE 1045) |
| OEM Reference | ZF 4661.134.004 |
| Seal Type | Viton O-Ring (compatible with O-RING) |
Compatibility
This converter assembly is engineered for the ZF WG 90 and WG 94 series powershift transmissions. Based on its design and mounting flange pattern, the 4661.134.004 is compatible with the following models: WG180, WG200, WG210, and WG250. It is also used in select WG 94 variants found in 6–8 ton wheel loaders and telehandlers. The assembly requires the TUBE for fluid routing and the CYLINDRICAL PIN for precise alignment during installation. Always verify your transmission serial number before ordering.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4661101032 | TRANSMISSION HOUSING | Encloses gear train and converter assembly |
| 4661301047 | HOUSING II | Intermediate housing for converter support |
| 4661301093 | TUBE | Fluid supply tube to converter |
| 0631306174 | CYLINDRICAL PIN | Alignment dowel for housing assembly |
| 0769123894 | TYPE PLATE | Identification plate for transmission model |
| 0750100022 | SCREW PLUG | Seals oil passage ports |
| 0636302602 | SCREW PLUG | Drain or fill plug for converter housing |
| 0634100633 | O-RING | Seals converter-to-housing interface |
| 4661301041 | NOZZLE | Oil spray nozzle for clutch cooling |
| 4661301062 | NOZZLE | Secondary oil spray nozzle |
