Overview
The ZF 4646.352.138 GEAR is a critical power-transfer component within the WG251 series transmission assembly. This OEM genuine part is engineered to mesh precisely with adjacent shafts, converting rotational input into the correct torque output for heavy-duty industrial applications. As a hardened steel gear, it sits within the planetary gearset or countershaft cluster, directly influencing shift timing and load distribution. The SKU 4646.352.138 is manufactured to ZF’s original tolerances, ensuring seamless integration with the TRANSMISSION HOUSING and the HOUSING that encloses the rotating assembly. Replacing a worn gear with this exact OEM part restores factory-specified gear ratios and eliminates driveline backlash.
Symptoms of Failure
- Whining or howling noise during acceleration: A worn 4646.352.138 gear often produces a high-pitched metallic whine that increases with engine RPM, indicating tooth surface pitting or spalling.
- Intermittent gear slipping under load: When the gear’s tooth profile wears unevenly, the transmission may momentarily lose torque transfer, causing a slipping sensation during uphill climbs or heavy hauling.
- Metal particles in transmission fluid: Flaking or chipped gear teeth shed ferrous debris into the oil, visible during routine fluid changes or as sludge on the COVER magnet.
- Hard shifting or delayed engagement: Worn gear teeth disrupt synchronizer timing, leading to clunky shifts or a noticeable pause when moving from neutral to drive.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4646.352.138 |
| Material | Case-hardened alloy steel (20MnCr5 equivalent) |
| Weight | 1.85 kg (4.08 lbs) |
| Outside Diameter | 98.4 mm |
| Tooth Count | 32 teeth (helical) |
| Face Width | 22.5 mm |
| OEM Reference | ZF 4646.352.138 |
| Hardness | 58-62 HRC |
Compatibility
This gear is specifically designed for the ZF WG251 series transmission, commonly found in medium-duty trucks, buses, and off-highway equipment. Based on its tooth geometry and spline interface, the 4646.352.138 is also compatible with the following ZF models: WG180, WG200, WG211, and WG250. It directly replaces the original gear in the main shaft cluster. For proper installation, ensure the CAP SCREW torque values are followed per ZF service manual specifications.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4646101072 | TRANSMISSION HOUSING | Encloses and supports all gear train components |
| 4646301201 | HOUSING | Intermediate housing for bearing and shaft alignment |
| 4646301166 | COVER | Seals the housing and retains lubricant |
| 0636101051 | CAP SCREW | Fastens housing and cover assemblies |
| 4646201018 | COVER SHEET | Protective sheet for internal oil passages |
| 4646301277 | SCREEN SHEET | Filters debris from circulating transmission fluid |
| 4646201019 | COVER SHEET | Secondary sealing sheet for valve body |
| 0730365125 | TYPE PLATE | Identification plate with serial number |
| 0631311009 | GROOVED STUD | Alignment stud for precise housing positioning |
| 0636010216 | HEXAGON SCREW | General-purpose fastener for transmission assembly |
ZF 4646.352.138 GEAR – Gear RFQ Support
ZF 4646.352.138 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 4646.352.138 when sending your RFQ. PartsZF can review dotted, spaced, and compact number formats against the available product and documentation records.
Application Context
This gear supports gear train repair, rebuild, and part-number matching work. Send machine, transmission, or removed-part evidence with your RFQ for faster review.
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 | 4646.352.138 |
|---|---|
| Normalized SKU | 4646352138 |
| Part name | 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
