Overview
The ZF 4644.303.538 OUTPUT FLANGE is a critical driveline component engineered specifically for the WG 200 Series powershift transmission. This OEM genuine part serves as the mechanical interface between the transmission output shaft and the driveshaft, transferring rotational torque from the gearbox to the vehicle’s axles. Machined from high-strength forged steel, the flange features a precision-splined bore that mates directly to the output shaft, secured by a 0636021036 HEXAGON SCREW and integrated washer. The SKU 4644.303.538 is factory-balanced to minimize vibration at high RPM, ensuring smooth power delivery in heavy-duty applications such as construction loaders, forklifts, and agricultural tractors.
Symptoms of Failure
- Transmission fluid leaks at the output shaft seal: A worn or cracked output flange allows oil to seep past the seal, leaving puddles under the vehicle and reducing lubrication levels.
- Driveline vibration during acceleration: Flange wear or spline damage creates imbalance, causing noticeable shuddering through the chassis when engaging gears.
- Gear slipping or delayed engagement: Excessive play between the flange and output shaft leads to torque loss, making the transmission hesitate or slip under load.
- Metallic grinding noise from the transmission rear: Severe spline wear or flange cracking produces audible metal-on-metal contact, indicating imminent failure.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number (SKU) | 4644.303.538 |
| OEM Reference | ZF 4644.303.538 |
| Material | Forged alloy steel (C45 or equivalent) |
| Weight | Approx. 2.8 kg (6.2 lbs) |
| Outer Diameter | 180 mm |
| Pilot Bore Diameter | 45 mm |
| Bolt Circle Diameter | 150 mm |
| Number of Bolt Holes | 8 |
| Surface Treatment | Zinc-plated / phosphate-coated |
| Compatible Seal Type | Single-lip or double-lip oil seal |
Compatibility
This output flange is designed for the ZF WG 200 Series transmission family, including the WG180, WG200, and WG210 models commonly found in telehandlers, wheel loaders, and industrial tractors. It directly replaces the original flange on units manufactured from 2005 onward. For proper installation, ensure the 4644105424 DISCONNECTION coupling is aligned correctly, and verify that the 4644101224 TRANSMISSION HOUSING or 4644301346 TRANSMISSION HOUSING is free of cracks or distortion before mounting the flange.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644105424 | DISCONNECTION | Coupling for output shaft disconnect |
| 0636021036 | HEXAGON SCREW | Fastener for flange retention |
| 4644101224 | TRANSMISSION HOUSING | Main gearbox casing |
| 4644301346 | TRANSMISSION HOUSING | Rear housing section |
| 0730365067 | TYPE PLATE | Identification label |
| 4644106300 | SHIFT SYSTEM | Gear selection mechanism |
| 4644306500 | COVER PLATE | Access cover for valve block |
| 4644159311 | SHIFT SYSTEM | Secondary shift actuator |
| 4644306563 | VALVE BLOCK | Hydraulic control manifold |
| 4644306408 | WASHER | Sealing or shim washer |
