Overview
The ZF 4644.036.213 6 WG 201 Powershift Transmission Assembly is a complete, factory-grade unit designed for heavy-duty off-highway machinery. As the core hydraulic-mechanical assembly in the WG 201 series, this unit integrates the clutch packs, planetary gear sets, and valve body into a single, ready-to-install package. The SKU 4644.036.213 replaces worn or failed assemblies, restoring full power flow from the torque converter to the driveline. This assembly sits directly between the engine bellhousing and the output flange, serving as the central power distribution module. For a full rebuild, this unit is typically mounted within a robust TRANSMISSION HOUSING to ensure structural integrity under high torque loads.
Symptoms of Failure
- Delayed or harsh engagement: When the assembly wears, internal clutch piston seals fail, causing a noticeable lag when shifting from neutral to forward or reverse. This is a common symptom of a failing 6 WG 201 unit.
- Loss of power under load: Slipping gears during heavy pulling or climbing indicate worn friction discs within the assembly. Operators often report the engine revving without corresponding wheel speed.
- External oil leaks near the bellhousing: Cracks in the assembly housing or failed gaskets allow transmission fluid to escape. This often requires inspecting the TRANSMISSION HOUSING for damage during replacement.
- Unusual whining or grinding noises: Worn bearings or planetary gear damage inside the assembly produce metallic sounds, especially in lower gears.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number | 4644.036.213 |
| Series | WG 201 |
| Type | 6-Speed Powershift Assembly (Complete) |
| Dry Weight (approx.) | 185 kg (408 lbs) |
| Overall Length | 620 mm |
| Housing Material | High-Grade Cast Iron |
| OEM Reference | ZF 4644.036.213 |
| Torque Capacity | Up to 1,200 Nm |
| Fluid Capacity | 18 Liters (system dependent) |
Compatibility
This complete unit is engineered specifically for the ZF WG 201 transmission series. It is directly compatible with models including the WG 180, WG 200, and WG 201 variants found in loaders, graders, and material handlers. The assembly also fits select WG 211 configurations with minor modifications. When installing, ensure the THREADED BUSH is torqued correctly to secure the output shaft, and use a new SCREW PLUG to seal the pressure test port. This unit is not backward-compatible with the older WG 120 series without a full adapter kit.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101160 | TRANSMISSION HOUSING | Encloses the gear assembly and supports bearings |
| 4644301323 | TRANSMISSION HOUSING | Alternate housing variant for WG 201 |
| 4644301189 | THREADED BUSH | Secures output shaft alignment |
| 4475280043 | SCREW PLUG | Seals hydraulic test ports |
| 0634306198 | O-RING | Prevents fluid leaks at housing joints |
| 0730365067 | TYPE PLATE | Identification label for the assembly |
| 4644301161 | COVER PLATE | Protects the valve body area |
| 0636100621 | HEXAGON SCREW | Fastens housing components |
| 0631610020 | SET SCREW | Adjusts clutch pack preload |
| 0501218540 | BREATHER | Vents internal pressure |
