Overview
The ZF 4475.280.233 PIPE UNION is a critical hydraulic connection component engineered for the lubrication and cooling circuits within ZF heavy-duty transmissions. This OEM genuine part, identified by SKU 4475.280.233, serves as a sealed junction between the transmission housing and the oil cooler lines, ensuring uninterrupted fluid flow to high-stress gear sets and bearings. Typically located on the upper or side casing of the transmission, this union prevents pressure loss and maintains the thermal balance required for sustained operation in construction machinery. When installed alongside a 5838109012: DIFFERENTIAL, it supports the precise oil delivery needed for differential lubrication under heavy loads.
Symptoms of Failure
- Hydraulic fluid seepage at the union joint: A visible oil film or drip around the pipe union connection indicates a compromised seal, often leading to low transmission fluid levels and overheating.
- Erratic gear engagement under load: Insufficient oil pressure from a leaking union can cause delayed or harsh shifting, particularly when operating excavators or wheel loaders on inclines.
- Elevated transmission operating temperature: A cracked or corroded 4475.280.233 union disrupts oil flow to the cooler, triggering thermal warnings and potential damage to the 0750117075: TAPER ROLLER BEARING assembly.
- Whining noise from the differential area: Starvation of lubricant due to a failed pipe union produces metallic whining sounds, especially during turns, as the 2093209023: DIFFERENTIAL components lose adequate oil film.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4475.280.233 |
| Material | Steel with zinc-nickel plating |
| Connection Thread | M22 x 1.5 (male) |
| Hex Size | 27 mm |
| Weight | 0.12 kg (0.26 lbs) |
| OEM Reference | ZF 4475.280.233 |
| Seal Type | O-ring (included) |
Compatibility
This pipe union is designed for ZF powershift transmissions commonly used in construction machinery, including the WG180, WG200, and WG310 series. It also fits select 4WG-200 and 6WG-310 models where oil cooler lines interface with the 5838300626: DIFFERENTIAL HOUSING. Always verify the thread pitch and O-ring groove dimensions against your transmission’s service manual before installation.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 5838109012 | DIFFERENTIAL | Distributes torque to axle shafts |
| 0750117075 | TAPER ROLLER BEARING | Supports axial and radial loads on shafts |
| 2093209023 | DIFFERENTIAL | Provides speed differentiation between wheels |
| 5838300626 | DIFFERENTIAL HOUSING | Encloses differential gear set |
| 0631329088 | SPRING PIN | Secures shift fork alignment |
| 5838300811 | THRUST WASHER | Reduces axial friction in gear stacks |
| 5838300721 | AXLE BEVEL GEAR | Transfers power to wheel axles |
| 5838300633 | AXLE | Transmits rotational force to hubs |
| 5838300753 | THRUST WASHER | Controls end-play in planetary sets |
| 5838300818 | THRUST WASHER | Prevents gear-to-housing contact |
Frequently Asked Questions
Q: Can the 4475.280.233 pipe union be reused after removal?
A: ZF recommends replacing the O-ring seal and inspecting the union for thread galling or corrosion. Reuse is not advised if the sealing surface shows pitting or if the hex is rounded.
Q: What torque should be applied to this pipe union?
A: Tighten to 35–40 Nm (25–30 lb-ft) using a crowfoot wrench. Over-torquing can distort the union and cause leaks at the differential housing interface.
Q: Does this part fit the ZF 4WG-180 transmission?
A: Yes, it is compatible with the 4WG-180, 4WG-200, and 6WG-310 series. Confirm the oil cooler line routing matches your specific machine model.
📞 Need this part? Contact our ZF specialists:
Email: info@partszf.com |
Phone: +86 158 2286 3467 |
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