Overview
The ZF 4644.108.062 COUNTERSHAFT is a critical internal component engineered specifically for the WG 200 series of heavy-duty transmissions. This OEM genuine part functions as the primary torque-transfer shaft, synchronizing gear rotation and distributing engine power through the transmission’s planetary gear sets. Positioned centrally within the gear train, the countershaft interfaces directly with the 4644105424: DISCONNECTION mechanism and the 4644303538: OUTPUT FLANGE to ensure seamless power delivery. The SKU 4644.108.062 is precision-machined to ZF’s exacting tolerances, making it an indispensable element for maintaining driveline integrity in demanding industrial applications.
Symptoms of Failure
When the ZF 4644.108.062 countershaft begins to wear, operators often notice distinct operational issues. Persistent gear grinding during shifts is a primary indicator, as the shaft’s splines lose their precise engagement. Another common symptom is vibration under load at highway speeds, which can be traced to bearing surface degradation on the shaft. Intermittent loss of drive or transmission slipping occurs when the countershaft’s alignment with the 4644101224: TRANSMISSION HOUSING becomes compromised. Finally, metallic debris in the transmission fluid signals advanced wear, often requiring immediate replacement of the countershaft and associated components like the 0636021036: HEXAGON SCREW fasteners.
Technical Specifications
| Specification | Detail |
|---|---|
| Part Number (SKU) | 4644.108.062 |
| Product Type | Countershaft (Intermediate Shaft) |
| Material | Case-hardened alloy steel (20MnCr5 equivalent) |
| Overall Length | Approx. 420 mm |
| Diameter (Bearing Journals) | 55 mm / 60 mm |
| Spline Count | 24-tooth involute spline |
| Weight | 4.8 kg (10.6 lbs) |
| OEM Reference | ZF 4644.108.062 (Genuine) |
| Hardness | 58-62 HRC (surface) |
Compatibility
This countershaft is engineered for the ZF WG 200 series transmissions, which are widely used in municipal trucks, construction equipment, and medium-duty buses. Based on its design and spline configuration, the 4644.108.062 is also compatible with the WG 180 series and select variants of the WG 210 series. It is not cross-compatible with the Ecomat or AS Tronic families. For proper installation, ensure the 4644303538: OUTPUT FLANGE is inspected for wear, and all 0636021036: HEXAGON SCREW fasteners are torqued to factory specifications.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644105424 | Disconnection | Engages/disengages countershaft from output |
| 4644303538 | Output Flange | Transfers torque to driveshaft |
| 0636021036 | Hexagon Screw | Secures housing and flange assemblies |
| 4644101224 | Transmission Housing | Main structural casing for gear train |
| 4644301346 | Transmission Housing | Alternate housing variant for WG200 |
| 0730365067 | Type Plate | Identification and serial number plate |
| 4644106300 | Shift System | Controls gear selection and engagement |
| 4644306500 | Cover Plate | Seals transmission housing access point |
| 4644159311 | Shift System | Secondary shift actuator assembly |
| 4644306563 | Valve Block | Hydraulic control for shift modulation |
