Overview
The ZF 4644.004.208 4 WG 180(500) Powershift Transmission Assembly is a complete, fully assembled unit designed for heavy-duty off-highway applications. This SKU 4644.004.208 integrates the main drive housing, clutch packs, and hydraulic control system into a single drop-in replacement for the WG 180 series. It serves as the central power transfer module, converting engine torque into controlled wheel or implement motion. The assembly sits directly between the engine bell housing and the final drive, managing gear selection under load without power interruption. For proper sealing and structural integrity, this unit is paired with the 4644101208: TRANSMISSION HOUSING and the 4644301333: HOUSING, which form the outer casing and support the internal planetary gear sets.
Symptoms of Failure
- Delayed engagement or gear slipping under load: When the internal clutch discs or seals wear, the transmission hesitates before engaging forward or reverse, or slips during heavy pulling. This often accompanies a burnt clutch smell.
- External oil leaks at housing seams: Cracks or gasket failures in the main housing cause fluid to weep from the joint between the transmission and the TRANSMISSION HOUSING. Look for drips near the bell housing interface.
- Erratic shifting or loss of hydraulic pressure: A failing pump or valve body within the assembly leads to inconsistent shift points or a complete loss of drive. This is often accompanied by whining noises from the hydraulic system.
- Metal debris in the transmission fluid: Worn bearings or gear teeth produce metallic particles visible on the dipstick or drain plug. This indicates internal mechanical failure requiring immediate replacement.
Technical Specifications
| Specification | Value |
|---|---|
| OEM Part Number | 4644.004.208 |
| Series | WG 180 (4 WG 180(500)) |
| Weight (approx.) | 385 kg (849 lbs) |
| Overall Length | 720 mm |
| Overall Width | 510 mm |
| Overall Height | 580 mm |
| Housing Material | Cast Iron (GGG-40) |
| Input Torque Capacity | 500 Nm (peak) |
| Fluid Capacity | 22 liters (approx.) |
| OEM Reference | ZF 4 WG 180(500) |
Compatibility
This complete unit is engineered specifically for the ZF WG 180 series powershift transmissions, including the 4 WG 180(500) variant. It is also compatible with the WG 200 series when used with the appropriate 4644301257: ADAPTER. The assembly fits ZF models used in construction loaders, telescopic handlers, and agricultural tractors from manufacturers such as Case, New Holland, and JCB. Always verify the identification tag; the 0730365125: TYPE PLATE provides the exact model code. For secure mounting, use the 0631311009: GROOVED STUD to fasten the assembly to the engine flywheel housing.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101208 | TRANSMISSION HOUSING | Main outer casing for gear and clutch assembly |
| 4644301333 | HOUSING | Rear housing supporting output shaft and bearings |
| 0730365125 | TYPE PLATE | Identification tag with model and serial number |
| 0631311009 | GROOVED STUD | Fastener for engine-to-transmission connection |
| 0636305019 | SCREW PLUG | Seals fluid drain and fill ports |
| 4644301247 | THREADED BUSH | Provides wear-resistant thread insert for housing |
| 0634303485 | O-RING | Seals housing joint against oil leaks |
| 4644301257 | ADAPTER | Allows fitment to different engine bell housings |
| 0634306023 | O-RING | Seals adapter-to-housing interface |
| 4644106231 | SHIFT SYSTEM | Hydraulic valve and actuator assembly for gear selection |
