Overview
The ZF 4644.203.009 OUTPUT GEAR is a critical drivetrain component engineered specifically for the WG 180 series powershift transmission. This OEM genuine part transfers rotational force from the planetary gear set to the output shaft, directly influencing torque delivery to the driveline. Positioned within the rear section of the transmission housing, this gear meshes precisely with the 4644105475: DISCONNECTION mechanism to ensure smooth engagement and disengagement of power. The SKU 4644.203.009 is manufactured to ZF’s original tolerances, guaranteeing a direct fit without modification. Its robust construction withstands high cyclic loads, making it indispensable for heavy-duty industrial applications where reliability is non-negotiable.
Symptoms of Failure
- Audible gear whine or grinding during load shifts: Worn teeth on the 4644.203.009 produce a distinct high-pitched noise, often mistaken for bearing failure. This symptom worsens under acceleration, indicating uneven tooth contact.
- Intermittent power loss or gear slipping: A damaged output gear fails to maintain positive engagement with the 4642303097: OUTPUT FLANGE, causing momentary torque interruptions. Operators may notice RPM spikes without corresponding speed increases.
- Metallic debris in transmission fluid: Flaking or pitting on the gear surface sheds microscopic steel particles into the oil. Routine magnetic drain plug inspections reveal fine metallic sludge, a clear indicator of gear degradation.
- Vibration through the chassis at specific speeds: Eccentric wear on the output gear creates harmonic oscillations that transmit through the 4644101134: TRANSMISSION HOUSING, felt as a rhythmic shudder between 20-40 km/h.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4644.203.009 |
| OEM Reference | ZF 4644.203.009 |
| Material | Case-hardened alloy steel (20MnCr5 equivalent) |
| Tooth Count | 37 (helical, ground finish) |
| Pitch Diameter | 148.5 mm |
| Face Width | 42 mm |
| Weight | 3.85 kg |
| Hardness | 58-62 HRC (core) |
| Mounting Type | Splined bore with 0636020211: HEXAGON SCREW retention |
Compatibility
This output gear is primarily designed for the ZF WG 180 series, including WG180, WG180-2, and WG180-3 variants. It also retrofits into select WG 200 models (WG200-1, WG200-2) when used with the corresponding 4642303097: OUTPUT FLANGE. Cross-reference with ZF parts catalogs confirms interchangeability with earlier WG 160 series units after 1998. Always verify the spline count and pilot bore diameter against your existing assembly before installation.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644105475 | DISCONNECTION | Engages/disengages output gear from driveline |
| 4642303097 | OUTPUT FLANGE | Transfers torque from gear to driveshaft |
| 0636020211 | HEXAGON SCREW | Secures output gear to shaft |
| 4644101134 | TRANSMISSION HOUSING | Encloses gear assembly |
| 4644301349 | HOUSING | Secondary cover for output section |
| 0730365125 | TYPE PLATE | Identification tag for transmission model |
| 0631311009 | GROOVED STUD | Alignment dowel for housing mating |
| 0636305019 | SCREW PLUG | Seals oil passages in gear area |
| 4644301247 | THREADED BUSH | Reinforces bolt holes in housing |
| 0634303485 | O-RING | Prevents oil leakage at gear interface |
ZF 4644.203.009 OUTPUT GEAR – Gear RFQ Support
ZF 4644.203.009 OUTPUT 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 4644.203.009 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 | 4644.203.009 |
|---|---|
| Normalized SKU | 4644203009 |
| Part name | OUTPUT 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
