Overview
The ZF 4143.303.028 HELICAL GEAR is a precision-machined component engineered for the auxiliary drive and oil pump systems within the WG100, WG130, and WG131 transmission series. This OEM genuine part, identified by SKU 4143.303.028, meshes directly with the countershaft to reduce rotational noise and distribute torque smoothly across the gear train. It sits inside the main housing assembly, where it interfaces with the 4143101009: HOUSING and the 4143301025: HOUSING to maintain correct gear lash and axial alignment. The helical tooth profile ensures constant contact, minimizing vibration and extending the service life of the entire transmission.
Symptoms of Failure
- Whining or howling noise during acceleration: Worn tooth flanks on the 4143.303.028 create a high-pitched whine that intensifies under load, often mistaken for bearing failure.
- Intermittent gear slippage in auxiliary drive: Excessive backlash from a worn helical gear causes the PTO or oil pump to lose engagement, resulting in erratic hydraulic pressure.
- Metal particles in transmission fluid: Flaking or pitting on the gear surface deposits ferrous debris into the sump, which can clog the 0634313603: O-RING seals and accelerate wear on adjacent shafts.
- Oil seepage near the gear housing interface: A worn gear can cause misalignment, stressing the 4475280018: SCREW PLUG and leading to fluid loss around the housing joint.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4143.303.028 |
| Gear Type | Helical, Right-Hand |
| Outside Diameter | 98.5 mm |
| Face Width | 28.0 mm |
| Bore Diameter | 25.4 mm |
| Material | Case-Hardened Alloy Steel (16MnCr5) |
| Weight | 0.85 kg |
| OEM Reference | ZF 4143.303.028 |
| Heat Treatment | Carburized & Tempered to HRC 58-62 |
Compatibility
This helical gear is a direct OEM replacement for the following ZF transmission models: WG100, WG130, WG131, WG180, and WG200. It also fits select HL 100 Series and HL 270 Series auxiliary drives. Always verify the gear count and shaft spline configuration before installation. For complete sealing, pair this gear with a new 0634313591: O-RING and inspect the 0501342341: SUPPORT RING for wear.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4143101009 | HOUSING | Encloses the gear set and maintains shaft alignment |
| 4143301025 | HOUSING | Rear housing section supporting the output shaft |
| 0634313603 | O-RING | Seals the gear housing interface against fluid leaks |
| 4475280018 | SCREW PLUG | Closes oil passages and prevents contamination |
| 0501342341 | SUPPORT RING | Provides axial support for the helical gear hub |
| 4143298457 | SEAL KIT | Contains all gaskets and O-rings for a full overhaul |
| 0634313591 | O-RING | Secondary seal for the gear shaft bore |
| 0636101068 | CAP SCREW | Fastens the housing cover to the transmission case |
| 4143221013 | THROTTLE VALVE | Regulates hydraulic flow to the gear clutch pack |
| 0634304484 | O-RING | Seals the throttle valve bore against pressure loss |
ZF 4143.303.028 HELICAL GEAR – Gear RFQ Support
Use ZF 4143.303.028 HELICAL GEAR as the reference when requesting gear support. Photos, visible markings, and transmission context help reduce sourcing uncertainty.
Part-Number Summary
Use ZF number 4143.303.028 when sending your RFQ. PartsZF can review dotted, spaced, and compact number formats against the available product and documentation records.
Application Context
- Illustration section: OUTPUT
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 | 4143.303.028 |
|---|---|
| Normalized SKU | 4143303028 |
| Part name | HELICAL 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: diagram. 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
