Overview
The ZF 4108.221.003 ADAPTER is a precision-machined interface component engineered to secure the hydraulic motor to the transmission housing in heavy-duty construction machinery. This OEM genuine part, identified by SKU 4108.221.003, sits between the pump drive and the main gearset, ensuring correct alignment and torque transfer. Without this adapter, the entire driveline assembly loses structural integrity, leading to misalignment and premature wear on adjacent components.
Symptoms of Failure
- Oil seepage at the motor-to-housing joint: When the adapter face distorts, hydraulic fluid escapes, creating visible drips under the machine.
- Intermittent gear slipping under load: A warped adapter causes the MOTOR to shift, resulting in erratic power delivery during excavation or lifting.
- Abnormal vibration from the transmission bell housing: Loose fitment generates harmonic chatter that worsens at higher RPMs.
- Difficulty engaging forward or reverse gears: Misalignment prevents the clutch pack from fully seating, producing a grinding sensation.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4108.221.003 |
| Material | High-tensile cast iron (GGG-40) |
| Outer Diameter | 210 mm |
| Inner Diameter | 85 mm |
| Thickness | 32 mm |
| Weight | 1.8 kg |
| OEM Reference | ZF 4108.221.003 |
| Surface Treatment | Zinc-phosphate coating |
Compatibility
This adapter is a direct fit for ZF WG180, WG200, and WG310 series transmissions commonly used in wheel loaders, telehandlers, and excavators. It also integrates with the HOUSING (part 4108101140) and the COVER (part 0501314793) to form a sealed assembly. For optimal longevity, pair it with a new BUSH (part 0501314799) during rebuilds.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4108101140 | HOUSING | Encloses the gear train and supports shaft bearings |
| 0501211694 | MOTOR | Converts hydraulic pressure into rotational force |
| 0501314793 | COVER | Seals the adapter cavity and retains lubricant |
| 0501314799 | BUSH | Reduces friction between the adapter and shaft |
| 0735370299 | TAPERED ROLLER BEARING | Handles axial and radial loads from the input shaft |
| 0501317874 | HOUSING | Secondary housing for the clutch pack assembly |
| 0501317875 | ROLLER | Needle roller for low-friction planetary gear support |
| 0501209497 | PISTON | Hydraulic piston that actuates clutch engagement |
| 0501317876 | COMPRESSION SPRING | Returns the piston to neutral position |
| 0501314823 | BUSH | Wear sleeve for the output shaft support |
