Overview
The ZF 4644.036.044 6 WG 201 Powershift Transmission Assembly | Complete Unit is a fully integrated, factory-spec drivetrain module designed for heavy-duty off-highway machinery. This complete assembly serves as the central power distribution hub, managing torque conversion and gear selection under high load conditions. The SKU 4644.036.044 represents a direct OEM replacement unit that eliminates the need for partial rebuilds, ensuring immediate operational reliability. It sits at the core of the transmission system, connecting the engine output to the final drive via a multi-speed planetary gearset. For proper sealing and structural integrity, this unit is paired with the 4644101160: TRANSMISSION HOUSING and the 4644301323: TRANSMISSION HOUSING, which provide the rigid casing for all internal components.
Symptoms of Failure
- Delayed engagement or gear slipping under load: When the complete unit wears, hydraulic pressure drops, causing hesitation when shifting from neutral to drive or reverse.
- External oil leaks at housing seams: Degraded seals within the assembly allow transmission fluid to escape, often pooling near the bell housing or pan rail.
- Erratic shifting or harsh clutch engagement: Worn internal clutches or valve body issues produce jarring shifts, especially during low-speed maneuvering.
- Overheating and burnt fluid odor: Internal friction from failing components generates excessive heat, leading to discolored fluid and a distinct burnt smell.
Technical Specifications
| Specification | Value |
|---|---|
| OEM Part Number | 4644.036.044 |
| Series | WG 201 (6 WG 201) |
| Type | Powershift Transmission Assembly (Complete Unit) |
| Dry Weight (approx.) | 185 kg (408 lbs) |
| Overall Length (approx.) | 620 mm |
| Overall Width (approx.) | 480 mm |
| Overall Height (approx.) | 510 mm |
| Housing Material | High-strength cast iron (GGG-40) |
| Seal Type | Viton® O-rings (see 0634306198: O-RING) |
| Identification | Includes 0730365067: TYPE PLATE |
| Cover Component | 4644301161: COVER PLATE |
| Fastener (Housing) | 0636100621: HEXAGON SCREW |
| Fastener (Internal) | 0631610020: SET SCREW |
| Ventilation | 0501218540: BREATHER |
Compatibility
This complete unit is engineered for the ZF WG 201 series powershift transmissions. It is directly compatible with models including the WG180, WG200, and WG210, which share the same bell housing pattern and input shaft spline count. The assembly also fits select variants of the 6 WG 201 family used in wheel loaders, graders, and industrial tractors. For proper installation, ensure the 4644301189: THREADED BUSH is correctly torqued, and the 4475280043: SCREW PLUG is fitted to seal the pressure test port.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101160 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4644301323 | TRANSMISSION HOUSING | Secondary housing for clutch pack assembly |
| 4644301189 | THREADED BUSH | Guides shift rod through housing wall |
| 4475280043 | SCREW PLUG | Seals hydraulic test or drain ports |
| 0634306198 | O-RING | Provides fluid-tight seal between housings |
| 0730365067 | TYPE PLATE | Identification tag with serial number |
| 4644301161 | COVER PLATE | Encloses valve body access area |
| 0636100621 | HEXAGON SCREW | Secures housing halves together |
| 0631610020 | SET SCREW | Locks internal adjustment rings |
| 0501218540 | BREATHER | Equalizes internal pressure and vents moisture |
