Overview
The ZF 4644.026.297 6 WG 200(555/5) Powershift Transmission Assembly is a complete, factory-matched unit designed for heavy-duty off-highway applications. This assembly integrates the main gear cluster, clutch packs, and hydraulic control components into a single, ready-to-install package. As a core element of the WG 200 Series, it manages torque distribution across six forward and one reverse gear, ensuring smooth power delivery under extreme loads. The SKU 4644.026.297 is the definitive OEM reference for this specific 555/5 ratio variant, guaranteeing correct fitment for ZF powershift systems. When replacing this unit, always inspect the 4644101216: TRANSMISSION HOUSING and the 4644301223: TRANSMISSION HOUSING for cracks or wear, as these housings directly support the assembly.
Symptoms of Failure
- Delayed or harsh gear engagement: When the assembly’s internal clutches or seals degrade, operators experience a noticeable lag between shifting and actual gear engagement, often accompanied by a jarring “clunk.”
- Intermittent loss of forward or reverse drive: Worn hydraulic pistons or valve body components within the assembly can cause the transmission to suddenly drop out of gear, particularly under heavy load or on inclines.
- Contaminated or dark transmission fluid: Internal friction material shedding from the clutch packs produces metallic debris and a burnt odor in the oil, visible on the dipstick or during a drain.
- Constant oil seepage from the bell housing area: Failed seals between the assembly and the 0730365067: TYPE PLATE or housing joints allow fluid to weep, leading to low oil levels and eventual overheating.
Technical Specifications
| Parameter | Specification |
|---|---|
| OEM Part Number | 4644.026.297 |
| Series | WG 200 (6 WG 200/555/5) |
| Assembly Type | Complete Powershift Unit |
| Dry Weight (approx.) | 185 kg (408 lbs) |
| Housing Material | High-Grade Cast Iron |
| Overall Length (approx.) | 620 mm |
| Input Torque Capacity | 555 Nm (peak) |
| Number of Gears | 6 Forward / 1 Reverse |
| OEM Reference | ZF 6 WG 200 |
Compatibility
This complete assembly is engineered for the ZF WG 200 Series of powershift transmissions. It is directly compatible with the WG 180 and WG 200 models used in telehandlers, wheel loaders, and industrial tractors. The 555/5 ratio variant is specifically calibrated for machines requiring high torque at low speeds. Always verify the serial number against your existing unit. During installation, ensure the 0631311009: GROOVED STUD is torqued to factory specifications to prevent alignment issues.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101216 | TRANSMISSION HOUSING | Encloses the gear train and supports bearings |
| 4644301223 | TRANSMISSION HOUSING | Alternate housing variant for specific WG200 builds |
| 0730365067 | TYPE PLATE | Identifies transmission model and serial number |
| 0631311009 | GROOVED STUD | Secures the assembly to the engine flywheel housing |
| 4644303060 | COVER PLATE | Seals the clutch access port on the housing |
| 4644303061 | COVER PLATE | Alternate cover plate for different housing configurations |
| 0634306525 | O-RING | Hydraulic seal between valve body and housing |
| 0636305026 | SCREW PLUG | Closes oil gallery ports during assembly |
| 4644301279 | SCREEN SHEET | Filters debris from the lubrication circuit |
| 4644301088 | SEALING CAP | Prevents contamination of unused hydraulic ports |
