Overview
The ZF 4644.036.049 6 WG 201 Powershift Transmission Assembly is a complete, factory-grade unit designed for heavy-duty off-highway machinery. This assembly integrates the full gear train, clutch packs, and hydraulic control system within a single robust package. As a direct replacement for the WG 201 series, the SKU 4644.036.049 serves as the central power transfer component, converting engine torque into precise, shiftable output for loaders, graders, and industrial vehicles. It mounts directly to the engine bellhousing and interfaces with the driveline through the output flange, ensuring seamless power delivery under extreme loads.
Symptoms of Failure
- Delayed or harsh gear engagement: When the assembly wears, operators experience a noticeable lag between shifting and actual gear engagement, often accompanied by a jarring clunk. This indicates internal clutch pack or hydraulic circuit degradation.
- Progressive oil leaks from housing seals: Worn gaskets or cracked casings cause transmission fluid to weep from the main joint. If you spot puddles under the bellhousing, inspect the TRANSMISSION HOUSING and TRANSMISSION HOUSING for stress fractures.
- Intermittent slipping under load: The transmission loses torque transfer during uphill travel or heavy pushing, often accompanied by rising oil temperature. This points to worn clutch discs or a failing torque converter within the assembly.
- Unusual whining or grinding noises: Metallic sounds from the transmission case, especially in neutral, signal bearing failure or gear tooth damage that requires immediate replacement of the complete unit.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | 4644.036.049 |
| Series | WG 201 (6-speed powershift) |
| Dry Weight (approx.) | 185 kg (408 lbs) |
| Overall Length | 620 mm |
| Overall Width | 480 mm |
| Overall Height | 510 mm |
| Housing Material | High-strength cast iron |
| OEM Reference | ZF 6 WG 201 |
| Fluid Capacity | ~12 liters (SAE 10W-30) |
Compatibility
This complete unit is engineered for the ZF WG 201 series, but it also serves as a direct upgrade or replacement for earlier WG 180 and WG 200 models due to shared mounting patterns and hydraulic interfaces. It is commonly found in ZF 6WG-201, 6WG-180, and 6WG-200 transmissions used in construction equipment from Volvo, Case, and Caterpillar. For proper sealing, always pair this assembly with a new O-RING on the input shaft and verify the TYPE PLATE matches your original unit. The THREADED BUSH and SCREW PLUG must be torqued to spec during installation to prevent leaks.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101160 | TRANSMISSION HOUSING | Main structural casing for gear cluster |
| 4644301323 | TRANSMISSION HOUSING | Secondary housing for clutch pack section |
| 4644301189 | THREADED BUSH | Wear-resistant insert for shift linkage |
| 4475280043 | SCREW PLUG | Seals hydraulic test ports |
| 0634306198 | O-RING | Prevents fluid leakage at shaft joints |
| 0730365067 | TYPE PLATE | Identification tag for model verification |
| 4644301161 | COVER PLATE | Protects valve body from debris |
| 0636100621 | HEXAGON SCREW | Fastens housing halves together |
| 0631610020 | SET SCREW | Locks shift fork position |
| 0501218540 | BREATHER | Equalizes internal pressure |
