Overview
The ZF 4651.353.021 SPUR GEAR is a critical power transmission component engineered for the WG 100 series transmission family. This OEM genuine part, identified by SKU 4651.353.021, sits within the intermediate shaft assembly, where it meshes directly with the main drive gear to transfer torque from the engine to the planetary gear sets. Precision-ground teeth ensure minimal backlash and quiet operation under heavy loads. This spur gear is housed securely within the 4651101006: TRANSMISSION HOUSING, which provides the rigid alignment necessary for long service life. When paired with the 4651301034: HOUSING, the gear maintains proper axial positioning, while the 0634303928: O-RING seals the interface against fluid ingress. For complete assembly integrity, the 4651301013: HOUSING supports the gear’s bearing journals.
Symptoms of Failure
When the 4651.353.021 spur gear begins to wear, operators often notice distinct performance issues. Whining or howling noise during acceleration is a primary indicator, caused by pitting or spalling on the gear teeth flanks. Intermittent gear slipping under load occurs when tooth profiles become worn, reducing the contact ratio and allowing momentary disengagement. Metal particles in the transmission oil filter signal advanced wear, as fragments from the gear surface contaminate the lubrication system. Finally, vibration through the shift lever or chassis indicates uneven tooth wear or a damaged gear bore, which can lead to catastrophic failure if ignored.
Technical Specifications
| Part Number | 4651.353.021 |
| Gear Type | Helical Spur Gear |
| Outside Diameter | 142.5 mm |
| Root Diameter | 128.3 mm |
| Face Width | 38.0 mm |
| Number of Teeth | 34 |
| Material | Case-Hardened Alloy Steel (20MnCr5) |
| Surface Hardness | 58-62 HRC |
| Weight | 2.85 kg |
| OEM Reference | ZF 4651.353.021 |
Compatibility
This spur gear is specifically designed for the ZF WG 100 series transmissions, including the WG100, WG120, and WG150 models. It also fits select variants of the WG180 and WG200 transmissions where the intermediate shaft gear ratio matches. Always verify the gear tooth count and shaft spline dimensions against your transmission’s service manual. The gear is not compatible with the older WG 80 series or the heavy-duty WG 250 series without modification to the 4651301015: SCREEN SHEET and 4651301035: SCREEN SHEET assemblies.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4651101006 | TRANSMISSION HOUSING | Main structural casing for gear alignment |
| 4651301034 | HOUSING | Intermediate shaft bearing support |
| 0634303928 | O-RING | Seals housing joint against oil leaks |
| 4651301013 | HOUSING | Rear bearing carrier for output shaft |
| 4651301015 | SCREEN SHEET | Fine mesh filter for oil return circuit |
| 4651301035 | SCREEN SHEET | Coarse debris screen for sump |
| 0630361028 | SEALING CAP | Closes unused hydraulic ports |
| 4475280060 | SCREW PLUG | Seals drain or fill holes |
| 0634303312 | O-RING | Seals screw plug against leakage |
| 0630361063 | SEALING CAP | Protects sensor ports from contamination |
ZF 4651.353.021 SPUR GEAR – Gear RFQ Support
ZF 4651.353.021 SPUR GEAR is handled as a gear-train sourcing item for transmission repair teams. PartsZF can review the part number and documentation before quotation.
Part-Number Summary
Use ZF number 4651.353.021 when sending your RFQ. PartsZF can review dotted, spaced, and compact number formats against the available product and documentation records.
Application Context
- Illustration section: COUPLING
Cross Reference Support
If you have an OEM number, old supplier number, or visible marking, include it with your RFQ so PartsZF can compare it with the available records.
Specification Snapshot
| ZF part number | 4651.353.021 |
|---|---|
| Normalized SKU | 4651353021 |
| Part name | SPUR GEAR |
| Product category | gear |
| RFQ support | Part-number lookup and documentation review |
| Media support | Product photo or diagram review when available |
Image and Documentation Notes
Current product media status: fallback. Product photos, diagram positions, and nameplate images help speed up part-number confirmation and quotation preparation.
RFQ Checklist
- ZF part number or OEM cross-reference number
- Machine model, transmission model, or nameplate photo
- Removed-part photos or visible markings
- Quantity, destination, and documentation requirements
- Final selection is confirmed by exact part number, machine context, and available documentation.
Related Parts
- ZF 4661.302.010 GEAR
- ZF 2094.306.024 GEAR SHIFT RAIL
- ZF 4642.353.026 SPUR GEAR
- ZF 4143.142.013 GEAR SHIFT SENSOR
- ZF 4143.142.022 GEAR SHIFT SENSOR
