Overview
The ZF 4660.003.044 4 WG 98 PS Powershift Transmission Assembly is a complete, factory-matched unit designed for heavy-duty off-highway machinery. This assembly integrates the main gear cluster, clutch packs, and hydraulic control components into a single ready-to-install package. As a core element of the WG 98 Series, it manages torque distribution across four forward and reverse speeds, ensuring smooth power delivery under extreme loads. The SKU 4660.003.044 identifies this specific assembly variant, which is engineered to replace worn or failed units in wheel loaders, graders, and industrial tractors. It interfaces directly with the TRANSMISSION HOUSING to form the structural backbone of the drivetrain, while the HOUSING II encloses the rear clutch section for contamination-free operation.
Symptoms of Failure
- Delayed or harsh gear engagement: When the 4660.003.044 assembly loses internal seal integrity, hydraulic pressure drops, causing a noticeable lag or jarring shift between forward and reverse ranges.
- Transmission overheating under load: Worn clutch plates within the assembly generate excessive friction, leading to fluid temperatures above 120°C and potential thermal damage to adjacent components.
- Intermittent power loss during uphill operation: Internal leakage past piston seals results in clutch slippage, particularly when the machine is under heavy torque demand on inclines.
- Metallic debris in transmission fluid: As gear teeth or bearing surfaces degrade, fine steel particles contaminate the oil, often visible during routine drain intervals.
Technical Specifications
| Parameter | Value |
|---|---|
| Assembly Weight (dry) | 185 kg (408 lbs) |
| Overall Length | 620 mm |
| Maximum Input Torque | 1,200 Nm |
| Clutch Plate Count | 12 (4 per pack) |
| Housing Material | Cast iron (GGG-40) |
| OEM Reference | ZF 4660.003.044 |
| Seal Type | PTFE lip seals |
Compatibility
This complete unit is specifically validated for the ZF WG 98 Series powershift transmissions. It is a direct fit for models including the WG98, WG180, and WG200 when used in 4-speed configurations. The assembly also supports the WG150 variant with minor adaptor plate modifications. For proper installation, ensure the CYLINDRICAL PIN is correctly aligned to the dowel holes in the housing, and the TYPE PLATE is transferred from the old unit for serial number traceability.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4660101015 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4660301054 | HOUSING II | Rear clutch housing section |
| 0631306174 | CYLINDRICAL PIN | Alignment dowel for housing mating |
| 0769123894 | TYPE PLATE | Identification and rating plate |
| 0750100022 | SCREW PLUG | Oil drain or fill port seal |
| 4660221029 | SUCTION TUBE | Oil pickup from sump to pump |
| 0634100317 | O-RING | Static seal for tube connections |
| 0636103273 | CAP SCREW | High-tensile fastener for housing |
| 0634306311 | O-RING | Seal for clutch piston cavity |
| 4660321029 | FIXING PLATE | Retains clutch pack in position |
