Overview
The ZF 4644.036.063 6 WG 201 Powershift Transmission Assembly is a complete, factory-matched unit designed for heavy-duty off-highway machinery. This assembly integrates the clutch packs, planetary gear sets, and hydraulic control components into a single ready-to-install package. As a core element of the WG 201 series, it manages torque distribution across six forward speeds and one reverse, enabling smooth power shifts under load. The SKU 4644.036.063 is the definitive replacement for worn-out assemblies, eliminating the need for piecemeal repairs. This complete unit interfaces directly with the TRANSMISSION HOUSING (part 4644101172) to form the structural backbone of the drivetrain, ensuring precise alignment of all rotating components.
Symptoms of Failure
- Erratic gear engagement or slipping under load: When the internal clutch discs or seals degrade, the transmission may hesitate or fail to hold a gear, particularly during uphill operation or when carrying rated loads.
- Contaminated or burnt transmission fluid: Friction material wear from the assembly can turn the oil dark and produce a burnt odor, indicating imminent internal failure.
- Delayed or harsh shifting: Worn valve body components within the assembly cause pressure irregularities, resulting in jarring shifts or a noticeable lag between gear changes.
- External oil seepage from the bell housing area: Cracks or fatigue in the assembly’s housing can lead to fluid leaks, often mistaken for a simple gasket failure.
Technical Specifications
| Parameter | Value |
|---|---|
| OEM Part Number | 4644.036.063 |
| Series | WG 201 (6 WG 201) |
| Assembly Type | Complete Powershift Unit |
| Estimated Dry Weight | 185 kg (408 lbs) |
| Overall Length | 620 mm |
| Housing Material | High-Grade Cast Iron |
| Input Torque Capacity | 1,200 Nm (885 lb-ft) |
| Number of Speeds | 6 Forward / 1 Reverse |
| Sealing System | O-Ring & Sealing Ring (see related parts) |
Compatibility
This complete assembly is engineered for the ZF WG 201 series transmissions, which are widely used in telehandlers, wheel loaders, and industrial tractors. It is directly compatible with models including the WG 180, WG 200, and WG 210, as well as all variants of the 6 WG 201 family. The unit also fits applications originally equipped with the TRANSMISSION HOUSING (part 4644301390) and the THREADED BUSH (part 4644301189). For final sealing of the assembly, the SCREW PLUG (part 0636302005) is required to prevent fluid loss from the main case ports.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101172 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4644301390 | TRANSMISSION HOUSING | Alternate housing variant for WG series |
| 4644301189 | THREADED BUSH | Guides and aligns shift mechanism |
| 0636302005 | SCREW PLUG | Seals hydraulic ports in the housing |
| 0634306198 | O-RING | Provides static seal between components |
| 0634801098 | SEALING RING | Dynamic seal for rotating shafts |
| 0730365067 | TYPE PLATE | Identification tag with serial number |
| 0631311009 | GROOVED STUD | Fastener for mounting accessories |
| 4644301161 | COVER PLATE | Encloses valve body access area |
| 0636100621 | HEXAGON SCREW | Secures cover plate and housings |
