Overview
The ZF 4644.026.173 WENDEGETRIEBE Powershift Transmission Assembly is a complete, fully assembled unit designed for the demanding environments of industrial material handling and construction machinery. As a core component of the WG 200 Series, this assembly integrates the reversing gear set and clutch pack system, enabling smooth directional shifts under load. The SKU 4644.026.173 represents a direct replacement unit that eliminates the need for complex internal rebuilds. This assembly interfaces directly with the TRANSMISSION HOUSING (4644101232) and the TRANSMISSION HOUSING (4644301282) to form the sealed driveline envelope. Proper sealing is ensured by the O-RING (0634306198) and the SCREW PLUG (4475280043), which are critical for maintaining hydraulic pressure integrity.
Symptoms of Failure
When the ZF 4644.026.173 WENDEGETRIEBE assembly begins to fail, operators typically notice three distinct symptoms. First, delayed or harsh directional engagement occurs when shifting from forward to reverse, often accompanied by a loud clunk. Second, intermittent loss of drive under load is common, where the machine hesitates or slips during acceleration on inclines. Third, hydraulic oil contamination with metallic debris is a clear indicator of internal clutch wear, visible when checking the fluid through the fill plug. These failure modes often necessitate replacement of the complete unit rather than individual seals.
Technical Specifications
| Specification | Detail |
|---|---|
| Part Number | 4644.026.173 |
| Assembly Type | WENDEGETRIEBE (Reversing Gear) Powershift |
| Dry Weight (approx.) | 48 kg (106 lbs) |
| Housing Material | High-Grade Cast Iron (GGG-40) |
| Input Torque Capacity | Up to 600 Nm |
| OEM Reference | ZF Friedrichshafen AG |
| Seal Type | PTFE Lip Seal with O-Ring Backup |
Compatibility
This complete unit is engineered for the ZF WG 200 Series transmissions, specifically the WG180, WG200, and WG210 variants commonly found in telescopic handlers, forklifts, and compact loaders. It is a direct fit for models requiring the 4644 prefix housing interface. The assembly is not compatible with older WG 100 series or the heavy-duty WG 300 series without significant modifications to the COVER PLATE (4644301298) and shift linkage. Always verify the transmission serial number against the ZF parts catalog before ordering.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101232 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4644301282 | TRANSMISSION HOUSING | Secondary housing for clutch pack |
| 4475280043 | SCREW PLUG | Seals hydraulic test ports |
| 0634306198 | O-RING | Hydraulic seal between housings |
| 0730365067 | TYPE PLATE | Identification plate for serial number |
| 4644301298 | COVER PLATE | Access cover for valve block |
| 4644106301 | SHIFT SYSTEM | Mechanical shift linkage assembly |
| 4644306507 | COVER PLATE | Bottom cover for oil pan |
| 4644159302 | SHIFT SYSTEM | Hydraulic shift spool assembly |
| 4644306560 | VALVE BLOCK | Hydraulic control manifold |
