Overview
The ZF 4644.102.131 INPUT for WG200 is a critical driveline component engineered to transfer torque from the engine directly into the transmission’s planetary gearset. Positioned at the front of the main housing, this OEM genuine input shaft absorbs high rotational stress and ensures precise alignment with the clutch packs. The SKU 4644.102.131 is machined from hardened alloy steel to withstand continuous heavy-duty cycles in construction and municipal vehicles. When paired with a robust TRANSMISSION HOUSING, this input shaft maintains concentricity and reduces vibration across the entire WG 200 Series.
Symptoms of Failure
- Torque converter shudder under load: A worn 4644.102.131 input shaft causes irregular engagement, leading to a pronounced vibration during acceleration.
- Delayed or harsh forward engagement: When the input splines strip or the bearing journal wears, operators experience a noticeable lag when shifting from neutral to drive.
- Metallic debris in transmission fluid: Flaking material from the input shaft’s hardened surface contaminates the oil, often accompanied by a whining noise from the pump area.
- Oil seepage at the front seal interface: Excessive radial play in the input shaft damages the seal lip, causing fluid loss around the bell housing.
Technical Specifications
| Part Number | 4644.102.131 |
| Material | Case-hardened alloy steel (20MnCr5 equivalent) |
| Overall Length | 285 mm |
| Spline Major Diameter | 32 mm |
| Bearing Journal Diameter | 45 mm |
| Weight | 2.8 kg |
| OEM Reference | ZF 4644.102.131 |
| Surface Hardness | 58-62 HRC |
Compatibility
This genuine ZF input shaft is designed primarily for the WG 200 Series transmissions, including the WG180 and WG200 models found in mid-size wheel loaders, forklifts, and airport ground support equipment. It also fits select ZF 4WG-200 and 6WG-200 variants. For proper sealing, always replace the O-RING and inspect the COVER PLATE for warpage during installation. The input shaft integrates directly with the TRANSMISSION HOUSING to form a rigid torque path.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101249 | TRANSMISSION HOUSING | Encloses gear train and supports input shaft bearings |
| 4644301402 | TRANSMISSION HOUSING | Alternate housing casting for WG200 variants |
| 4644301298 | COVER PLATE | Seals front access opening and retains input shaft |
| 0634306323 | O-RING | Prevents fluid leakage between housing and cover |
| 0636305026 | SCREW PLUG | Closes oil passages in the housing |
| 4644301279 | SCREEN SHEET | Filters debris from lubrication circuit |
| 4644301088 | SEALING CAP | Blocks unused ports on the housing |
| 4644159357 | SHIFT SYSTEM | Controls clutch engagement sequence |
| 4644306513 | COVER | Protects valve body area from contamination |
| 4644306555 | COVER | Secondary cover for auxiliary pump access |
