Overview
The ZF 0631.405.073 PLUG is a critical sealing component engineered for use in heavy-duty construction machinery transmissions. This OEM genuine part, identified by SKU 0631.405.073, functions as a threaded or press-fit closure within the transmission housing, preventing fluid leakage and contaminant ingress at access points or sensor ports. Designed to withstand high-pressure hydraulic environments and thermal cycling, this plug ensures the integrity of the lubrication system in ZF drivelines. When installed alongside a 2093109023 DIFFERENTIAL assembly, it maintains proper oil circulation and protects internal gears from debris.
Symptoms of Failure
- Hydraulic oil seepage around the plug housing: A worn or cracked 0631.405.073 plug often results in slow fluid loss, leaving visible stains on the transmission casing. This is a common long-tail search query for “ZF transmission oil leak at plug location.”
- Contaminated transmission fluid: When the plug fails to seal, dirt and moisture enter the system, causing premature wear on components like the 0750117075 TAPER ROLLER BEARING. Operators may notice gritty fluid during routine checks.
- Intermittent pressure loss in the hydraulic circuit: A compromised plug can lead to erratic clutch engagement or gear slipping under load, particularly in WG-series transmissions.
- Visible corrosion or thread damage: Exposure to extreme temperatures can deform the plug, making removal difficult and risking damage to the housing bore.
Technical Specifications
| Parameter | Specification |
|---|---|
| OEM Part Number | 0631.405.073 |
| Material | Hardened steel with zinc-nickel coating |
| Thread Size | M18 x 1.5 (estimated) |
| Overall Length | 22 mm |
| Hex Size | 17 mm (AF) |
| Weight | 0.04 kg |
| Sealing Type | O-ring face seal (integrated) |
| Operating Temperature Range | -40°C to +120°C |
Compatibility
This plug is a direct replacement for ZF transmission models in the WG180, WG200, and WG210 series, commonly deployed in wheel loaders, graders, and excavators. It is also compatible with certain Ecolife and AS-Tronic off-highway variants. For optimal sealing performance, always pair this part with a new 2093209096 DIFFERENTIAL gasket kit and inspect the 2093309073 DIFF.HOUSING for cracks during installation.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 2093109023 | DIFFERENTIAL | Distributes torque between axles |
| 0750117075 | TAPER ROLLER BEARING | Supports axial and radial loads |
| 2093209096 | DIFFERENTIAL | Secondary torque split unit |
| 2093309073 | DIFF.HOUSING | Encloses differential gears |
| 0631100223 | SPRING PIN | Secures shift fork alignment |
| 0730300820 | THRUST WASHER | Reduces axial friction |
| 4482360002 | AXLE BEVEL GEAR | Transfers power to wheel hubs |
| 2097309085 | DIFFERENTIAL AXLE | Connects differential to final drive |
| 5838300811 | THRUST WASHER | Controls gear end-play |
| 4482360001 | DIFFERENTIAL BEVEL GEAR | Meshes with axle bevel gear |
Frequently Asked Questions
Q: Can I reuse the 0631.405.073 plug after removing it?
A: ZF recommends replacing this plug with a new unit every time it is removed, as the O-ring seal deforms permanently during initial installation. Reuse risks micro-leaks under high pressure.
Q: What torque should I apply to this plug?
A: For the M18 x 1.5 thread, tighten to 45 N·m (33 ft-lb) using a torque wrench. Over-tightening can crack the differential housing bore.
Q: Is this plug compatible with synthetic transmission oils?
A: Yes. The zinc-nickel coating and NBR O-ring are fully resistant to synthetic lubricants used in ZF WG-series transmissions.
📞 Need this part? Contact our ZF specialists:
Email: info@partszf.com |
Phone: +86 158 2286 3467 |
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