Overview
The ZF 4644.306.280 DUCT PLATE is a precision-engineered internal component designed for the WG150, WG180, and WG200 series transmissions. This OEM genuine part functions as a critical fluid routing guide, directing oil flow within the transmission housing to ensure proper lubrication and cooling of planetary gear sets and clutch packs. The SKU 4644.306.280 sits between the main casing and the valve body assembly, creating a sealed channel that prevents cross-contamination of hydraulic circuits. Without this duct plate, the transmission cannot maintain the necessary oil pressure for smooth gear engagement. It is frequently replaced alongside the 4642101109: TRANSMISSION HOUSING or the 4642301205: TRANSMISSION HOUSING during major overhauls.
Symptoms of Failure
- Internal oil leaks causing low pressure: A warped or cracked duct plate allows pressurized fluid to bypass intended passages, leading to erratic shift timing and clutch slip under load.
- Overheating transmission fluid: When the duct plate fails to direct oil to the cooler circuit, the transmission rapidly exceeds normal operating temperatures, often triggering warning lights.
- Delayed engagement or harsh shifts: Debris or wear on the duct plate surface disrupts the oil flow to specific solenoids, resulting in a noticeable lag when shifting from Park to Drive or Reverse.
- Contaminated oil with metallic particles: A fractured duct plate can shed small metal fragments into the fluid, which then circulate through the valve body and damage other components like the 0631311009: GROOVED STUD.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number (SKU) | 4644.306.280 |
| Material | Die-cast aluminum alloy (A380) |
| Overall Length | 285 mm |
| Overall Width | 145 mm |
| Thickness | 8.5 mm |
| Weight | 0.72 kg (1.59 lbs) |
| OEM Reference | ZF 4644.306.280 |
| Surface Finish | Anodized, precision-machined sealing faces |
| Bolt Hole Pattern | 12 x M8 threaded bores |
Compatibility
This genuine ZF duct plate is engineered for the WG150, WG180, and WG200 series transmissions used in heavy-duty commercial vehicles, construction equipment, and agricultural machinery. It directly replaces the original factory-installed plate in the following models: WG150-3, WG150-4, WG180-3, WG180-4, WG200-3, and WG200-4. The part is also compatible with certain variants of the ZF Ecomat series when used with the appropriate 0730365125: TYPE PLATE for identification. Always verify the transmission serial number before ordering, as minor revisions exist between early and late production units.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4642101109 | TRANSMISSION HOUSING | Main casing that encloses all internal components |
| 4642301205 | TRANSMISSION HOUSING | Alternative housing for WG180 series |
| 0730365125 | TYPE PLATE | Identification plate for transmission model |
| 0631311009 | GROOVED STUD | Fastener for securing duct plate to housing |
| 4642301168 | SCREEN SHEET | Fine mesh filter for oil inlet |
| 4642301169 | SCREEN SHEET | Secondary filter for return line |
| 0636100621 | HEXAGON SCREW | Bolt for mounting duct plate assembly |
| 4642301186 | SCREEN SHEET | Large-area filter for sump |
| 4644106231 | SHIFT SYSTEM | Valve body and solenoid assembly |
| 4644306470 | GASKET | Sealing gasket for duct plate interface |
