Overview
The ZF 4644.103.080 OUTPUT for WG180 is a critical driveline component responsible for transferring torque from the transmission’s planetary gearset to the driveshaft. Positioned at the rear of the main case, this OEM genuine output shaft interfaces directly with the 4644101080: TRANSMISSION HOUSING and the 4644301333: HOUSING to ensure precise alignment and load distribution. The SKU 4644.103.080 is engineered to ZF’s original specifications, featuring hardened splines and a precision-ground bearing journal that minimizes vibration during high-torque operation. This part is essential for maintaining proper gear engagement and preventing premature wear in heavy-duty commercial vehicle transmissions.
Symptoms of Failure
- Oil leaks at the rear seal area: A worn output shaft bearing surface or damaged splines can cause seal distortion, leading to visible transmission fluid drips under the vehicle.
- Driveline vibration during acceleration: Excessive radial play in the output shaft creates a rhythmic shudder that intensifies under load, often misdiagnosed as a U-joint issue.
- Intermittent gear slipping in higher ranges: When the output shaft’s spline wear exceeds tolerance, torque transfer becomes inconsistent, causing the transmission to momentarily lose drive in 4th or 5th gear.
- Metallic debris in the transmission pan: Flaking from the hardened surface of the output shaft contaminates the hydraulic system, accelerating wear on the 4644106231: SHIFT SYSTEM components.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4644.103.080 |
| Overall Length | 412 mm |
| Shaft Diameter (bearing journal) | 55 mm |
| Spline Count | 21 (male, involute) |
| Material | Case-hardened alloy steel (20MnCr5) |
| Weight | 4.8 kg |
| OEM Reference | ZF 4644.103.080 |
| Surface Treatment | Phosphate coating with oil retention |
Compatibility
This output shaft is primarily designed for the ZF WG180 series, but it also fits select WG200 and WG160 variants produced between 2008 and 2020. The 4644.103.080 is compatible with transmissions that utilize the 0730365125: TYPE PLATE indicating a 6-bolt rear cover pattern. For proper installation, ensure the 0631311009: GROOVED STUD is torqued to 85 Nm when securing the output flange. This part is not compatible with the earlier WG180.1 series that used a 20-spline output configuration.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101080 | TRANSMISSION HOUSING | Encloses the planetary gearset and supports the output shaft |
| 4644301333 | HOUSING | Rear adapter housing for PTO mounting |
| 0730365125 | TYPE PLATE | Identification plate with transmission serial number |
| 0631311009 | GROOVED STUD | Locating pin for output flange alignment |
| 0636305019 | SCREW PLUG | Seals the oil gallery in the output shaft bore |
| 4644301247 | THREADED BUSH | Wear insert for the speed sensor port |
| 0634303485 | O-RING | Hydraulic seal between output shaft and housing |
| 4644106231 | SHIFT SYSTEM | Hydraulic valve body controlling clutch engagement |
| 4644306470 | GASKET | Paper gasket for the rear cover plate |
| 4644306194 | COVER PLATE | Protective shield over the output shaft nut |
