Overview
The ZF 4644.026.328 WENDEGETRIEBE Powershift Transmission Assembly is a complete, pre-assembled unit designed for the demanding environments of industrial and agricultural machinery. As a core component within the WG 200 Series, this assembly manages torque distribution and directional changes, enabling smooth forward and reverse operation without clutching. The SKU 4644.026.328 integrates the shift mechanism, clutch packs, and hydraulic passages into a single, ready-to-install module. This unit directly interfaces with the TRANSMISSION HOUSING to ensure precise alignment and oil flow, while the TYPE PLATE provides critical identification for service matching.
Symptoms of Failure
When the ZF 4644.026.328 assembly begins to degrade, operators often notice specific operational issues. Delayed or harsh engagement between forward and reverse gears is a primary indicator, often caused by worn clutch discs or degraded seals within the unit. Another common symptom is intermittent power loss under load, where the transmission momentarily slips during heavy pushing or pulling tasks. You may also observe contaminated transmission fluid with metallic debris, signaling internal wear of the planetary gears or bearings. Finally, erratic shifting or failure to hold a gear on inclines points to hydraulic pressure loss, which can be traced back to valve body wear inside this assembly.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number / SKU | 4644.026.328 |
| Assembly Type | WENDEGETRIEBE (Reversing) Powershift Unit |
| Series | WG 200 |
| Dry Weight (approx.) | 85 kg (187 lbs) |
| Housing Material | High-Strength Aluminum Alloy |
| Max Input Torque | 600 Nm (442 lb-ft) |
| Hydraulic Pressure Range | 12–18 bar (174–261 psi) |
| OEM Reference | ZF 4644.026.328 |
| Related Housing | 4644301308: TRANSMISSION HOUSING |
| Related Cover | 4644303060: COVER PLATE |
Compatibility
This complete unit is engineered for the ZF WG 200 Series of powershift transmissions, commonly found in telehandlers, wheel loaders, and specialized forestry equipment. It is directly compatible with models such as the WG180, WG200, and WG210. The assembly is designed to replace the reversing section in these gearboxes, working in tandem with the TRANSMISSION HOUSING and the COVER PLATE to seal the hydraulic circuit. Always verify the TYPE PLATE on your existing unit to confirm model and serial number alignment before installation.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101233 | TRANSMISSION HOUSING | Main structural casing for gear and shaft alignment |
| 4644301308 | TRANSMISSION HOUSING | Alternate housing variant for specific WG models |
| 0730365067 | TYPE PLATE | Identification tag with model and serial data |
| 4644303060 | COVER PLATE | Seals the clutch pack access port |
| 4644303061 | COVER PLATE | Alternative cover for different housing configurations |
| 4644106300 | SHIFT SYSTEM | Mechanical linkage for gear selection |
| 4644306500 | COVER PLATE | Top cover for hydraulic valve access |
| 4644159300 | SHIFT SYSTEM | Electronic shift actuator assembly |
| 4644306560 | VALVE BLOCK | Hydraulic control manifold for clutch modulation |
| 4644306408 | WASHER | Thrust washer for planetary gear support |
