Overview
The ZF 4616.303.025 SPUR GEAR is a precision-machined helical gear designed for the WG 65 series transmission. This OEM genuine part sits within the planetary gearset assembly, where it transfers torque from the input shaft to the output carrier, enabling smooth power delivery under heavy loads. The SKU 4616.303.025 is a direct replacement for worn gears in ZF’s WG65 drivetrain, ensuring correct tooth engagement and load distribution. When paired with a properly torqued HEXAGON SCREW and a sealed TRANSMISSION HOUSING, this spur gear maintains the precise gear mesh required for long service life in industrial applications.
Symptoms of Failure
- Whining or grinding noise during acceleration — Worn gear teeth produce a high-pitched whine or metallic grinding sound, especially under load. This is a common symptom of pitting or tooth face wear on the spur gear.
- Erratic shifting or gear slippage — As the gear loses its tooth profile, the transmission may hesitate or slip between ratios, causing inconsistent power delivery to the OUTPUT shaft.
- Metal particles in transmission fluid — Flakes or fine metallic debris found during oil changes indicate advanced wear of the spur gear’s hardened steel surface, often accompanied by damage to the OUTPUT FLANGE bearing surfaces.
- Vibration at specific RPM ranges — Uneven tooth wear creates imbalance in the gear train, producing noticeable vibration through the chassis or shift lever at cruising speeds.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4616.303.025 |
| Gear Type | Spur (Helical profile) |
| Material | Case-hardened alloy steel (20MnCr5 equivalent) |
| Outside Diameter | ~125 mm |
| Bore Diameter | ~35 mm |
| Face Width | ~28 mm |
| Weight | ~1.4 kg |
| OEM Reference | ZF 4616.303.025 |
| Hardness | 58-62 HRC (case depth 0.8-1.2 mm) |
Compatibility
This spur gear is specifically engineered for the ZF WG 65 series transmission family. It is compatible with the following models: WG65, WG120, WG180, and WG200. The gear is a critical component in the planetary gearset of these heavy-duty transmissions, commonly found in municipal trucks, construction vehicles, and agricultural machinery. Always verify the gear’s tooth count and spline profile against your existing assembly before installation.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4616105413 | OUTPUT | Transfers torque from gearset to driveline |
| 4616203017 | OUTPUT FLANGE | Connects output shaft to universal joint |
| 4616101117 | TRANSMISSION HOUSING | Encloses and supports gear train |
| 0636011038 | HEXAGON SCREW | Secures gear to shaft |
| 0636016015 | HEXAGON SCREW | Fastens housing cover |
| 0631306085 | CYLINDRICAL PIN | Aligns gear to carrier |
| 0634313118 | O-RING | Seals gear shaft bore |
| 0732611049 | FILTER INSERT | Removes debris from oil circuit |
| 0634303718 | O-RING | Seals output flange joint |
| 0636610082 | STUD | Mounts gear assembly to housing |
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