Overview
The ZF 4108.122.411 HYDRAULIC MOTOR is a critical power conversion component within the final drive assembly of heavy construction machinery. This OEM genuine part converts hydraulic fluid pressure into rotational mechanical torque, directly driving the wheel or track hub. Positioned between the transmission output and the planetary gear set, the SKU 4108.122.411 ensures precise speed control and high torque output for demanding earthmoving applications. Its robust construction withstands extreme pressure spikes and continuous operation in loaders, graders, and compactors.
Symptoms of Failure
- Intermittent drive loss or jerky motion: When the hydraulic motor wears, internal leakage causes uneven power delivery, often described as “transmission slipping under load” during uphill operation.
- External oil seepage from the motor housing: Worn shaft seals or housing cracks lead to visible hydraulic fluid leaks around the motor mounting flange, a common “ZF motor oil leak” complaint.
- Excessive noise during rotation: Grinding or whining sounds indicate damaged internal pistons or bearing wear, frequently reported as “whining hydraulic motor” in cold-start conditions.
- Reduced travel speed with no error codes: Gradual loss of maximum RPM despite full throttle suggests internal bypassing, often misdiagnosed as a pump issue.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4108.122.411 |
| Type | Axial Piston Hydraulic Motor |
| Displacement | 55 cc/rev (estimated) |
| Maximum Pressure | 420 bar (6,100 psi) |
| Housing Material | High-strength nodular cast iron |
| Weight | 14.2 kg (31.3 lbs) |
| OEM Reference | ZF 4108.122.411 |
| Mounting Flange | SAE 4-bolt B |
Compatibility
This hydraulic motor is designed for ZF WG series powershift transmissions commonly used in construction machinery. It directly fits the WG180, WG200, and WG211 models. The motor also integrates with certain WG150 and WG250 variants when paired with the correct 4108101112: HOUSING and 4108201177: HOUSING. For proper sealing, always replace the 0636302056: SCREW PLUG and inspect the 4108301304: BEARING COVER during installation.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4108101112 | HOUSING | Encloses the motor assembly |
| 4108201177 | HOUSING | Secondary motor housing section |
| 0636302056 | SCREW PLUG | Seals hydraulic ports |
| 4108301304 | BEARING COVER | Protects motor bearings |
| 4108306173 | GASKET | Prevents oil leaks at joints |
| 0750110040 | SHAFT SEAL | Seals rotating shaft |
| 4108102042 | INPUT | Power input shaft assembly |
| 4108302099 | PLANET CARRIER | Holds planetary gears |
| 4108302007 | BEARINGSHEET | Bearing shim set |
| 0635332196 | BALL BEARING | Supports rotating elements |
