Overview
The ZF 4475.280.071 PIPE UNION is a precision-engineered hydraulic connector designed to maintain sealed fluid pathways within ZF heavy-duty transmissions. This OEM genuine part sits at the junction between the transmission housing and the external oil cooler lines, ensuring that pressurized transmission fluid flows without restriction or leakage. The SKU 4475.280.071 is critical for preserving system pressure and preventing contamination ingress in construction machinery drivelines. When installed alongside a 5838109012: DIFFERENTIAL, this union guarantees that lubrication reaches the gear sets under all operating loads.
Symptoms of Failure
- Transmission fluid puddles under the vehicle: A degraded pipe union seal causes visible oil drips near the transmission cooler line connection points, especially after extended operation.
- Erratic gear engagement or slipping: When the 4475.280.071 loses its sealing integrity, hydraulic pressure drops, leading to delayed clutch pack application and inconsistent shifting.
- Overheating transmission fluid: A leaking union reduces oil flow to the cooler, causing the transmission to run hotter than normal and triggering warning lights on construction equipment dashboards.
- Foaming or aerated transmission fluid: Air drawn through a cracked pipe union mixes with the oil, producing a frothy appearance on the dipstick and reducing hydraulic efficiency.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4475.280.071 |
| Material | Steel with zinc-nickel plating |
| Thread Size | M22 x 1.5 (inlet/outlet) |
| Overall Length | 85 mm |
| Hex Size | 24 mm |
| Weight | 0.12 kg |
| OEM Reference | ZF 4475.280.071 |
| Seal Type | O-ring groove (O-ring not included) |
Compatibility
This pipe union is engineered for ZF WG series transmissions commonly found in wheel loaders, graders, and telehandlers. It is a direct fit for ZF WG180, WG200, and WG310 models. The 4475.280.071 also integrates with the 0750117075: TAPER ROLLER BEARING assembly and the 2093209023: DIFFERENTIAL unit, ensuring that the entire drivetrain receives consistent oil pressure. For complete rebuilds, pair this union with the 5838300626: DIFFERENTIAL HOUSING to restore factory-level sealing performance.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 5838109012 | DIFFERENTIAL | Distributes torque to axle shafts |
| 0750117075 | TAPER ROLLER BEARING | Supports rotating differential components |
| 2093209023 | DIFFERENTIAL | Secondary torque distribution unit |
| 5838300626 | DIFFERENTIAL HOUSING | Encloses differential gear set |
| 0631329088 | SPRING PIN | Secures gear alignment |
| 5838300811 | THRUST WASHER | Reduces axial friction |
| 5838300721 | AXLE BEVEL GEAR | Transfers power to wheels |
| 5838300633 | AXLE | Rotates wheel hubs |
| 5838300753 | THRUST WASHER | Controls gear end-play |
| 5838300818 | THRUST WASHER | Prevents axial movement |
Frequently Asked Questions
Q: Can the 4475.280.071 pipe union be reused after removal?
A: ZF recommends replacing the union with a new OEM part whenever the transmission is disassembled, as the sealing surface can deform during removal and cause future leaks.
Q: What torque specification should I use for installation?
A: Tighten the union to 45 Nm using a crowfoot wrench. Over-torquing can crack the housing, while under-torquing leads to oil seepage at the connection point.
Q: Does this part require a separate O-ring?
A: Yes. The 4475.280.071 does not include an O-ring. Use a compatible NBR O-ring (size 20×2.5 mm) to create a leak-proof seal between the union and the transmission housing.
📞 Need this part? Contact our ZF specialists:
Email: info@partszf.com |
Phone: +86 158 2286 3467 |
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