Overview
The ZF 4644.036.017 6 WG 201 Powershift Transmission Assembly is a complete, fully assembled unit designed for heavy-duty industrial applications. This SKU 4644.036.017 represents the core power transfer module within the WG 200 series family, integrating the main gear cluster, clutch packs, and hydraulic control system into a single, ready-to-install package. It sits at the heart of the drivetrain, converting engine torque into controlled, multi-speed output for wheel loaders, forklifts, and other off-highway machinery. When replacing this assembly, it is critical to inspect the supporting TRANSMISSION HOUSING (4644101160) and the TRANSMISSION HOUSING (4644301323) for cracks or wear, as these components directly affect alignment and oil sealing.
Symptoms of Failure
- Erratic gear engagement or slipping under load: Worn clutch discs or degraded seals inside the assembly cause the transmission to hesitate or lose torque during acceleration, especially in forward/reverse shifts.
- Internal hydraulic pressure loss: A failing unit often exhibits low line pressure, leading to delayed shifts and overheating. This is frequently accompanied by metal particles in the oil filter.
- External oil leaks from the bell housing or output flange: Cracks in the main housing or failed gaskets allow ATF to weep, creating visible drips and low fluid levels. Check the SCREW PLUG (4475280043) for proper torque, as a loose plug can mimic housing leaks.
- Unusual whining or grinding noises: Bearing fatigue or gear tooth damage inside the assembly produces a distinct metallic sound that worsens with RPM changes.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number / SKU | 4644.036.017 |
| Assembly Type | Complete Powershift Unit (6-speed forward / 3-speed reverse) |
| OEM Reference | ZF WG 201 |
| Dry Weight (approx.) | 185 kg (408 lbs) |
| Overall Length | 620 mm |
| Overall Width | 480 mm |
| Overall Height | 410 mm |
| Housing Material | High-strength cast iron (GGG-40) |
| Max Input Torque | 1,200 Nm |
| Fluid Capacity | 12.5 liters (ZF TE-ML 03 spec) |
| Seal Type | Viton® radial shaft seals |
Compatibility
This complete assembly is specifically engineered for the ZF WG 201 series. It is also compatible with earlier WG 180 and WG 200 models when used with the correct adapter kit, as the bolt pattern and input shaft spline count are shared across these generations. The unit directly replaces part numbers 4644.036.015 and 4644.036.016. For proper installation, always pair this assembly with a new O-RING (0634306198) and a THREADED BUSH (4644301189) to secure the hydraulic feed lines.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101160 | TRANSMISSION HOUSING | Main structural casing for gear and clutch assembly |
| 4644301323 | TRANSMISSION HOUSING | Secondary housing section for output shaft support |
| 4644301189 | THREADED BUSH | Hydraulic line connection adapter |
| 4475280043 | SCREW PLUG | Seals oil drain and pressure test ports |
| 0634306198 | O-RING | Seals housing joints against fluid leaks |
| 0730365067 | TYPE PLATE | Identification plate with serial number and specs |
| 4644301161 | COVER PLATE | Protects valve body and clutch access area |
| 0636100621 | HEXAGON SCREW | Fastens housing sections together |
| 0631610020 | SET SCREW | Locks adjustment rings on shift forks |
| 0501218540 | BREATHER | Vents internal pressure to prevent seal blowout |
