Overview
This genuine OEM ZF 0734.401.255 rectangular ring serves as a critical static seal within the differential and axle housing assembly of heavy-duty construction machinery transmissions. Engineered to withstand high-pressure oil environments and extreme thermal cycling, this precision-molded ring prevents fluid bypass between mating surfaces. The SKU 0734.401.255 is specifically designed to maintain a leak-proof barrier in the final drive section, ensuring consistent lubrication to internal components such as the 5838109012: DIFFERENTIAL and the 2093209023: DIFFERENTIAL assemblies. Without this seal, the transmission cannot maintain proper hydraulic pressure, leading to premature wear on adjacent rotating elements.
Symptoms of Failure
- External oil seepage around the differential housing: When the rectangular ring loses its elasticity, transmission fluid escapes past the seal face, leaving visible wet spots on the housing exterior.
- Low hydraulic pressure warnings during heavy load cycles: A degraded 0734.401.255 ring allows internal bypass, causing the transmission control system to register insufficient pressure for gear engagement.
- Contaminated lubricant from water ingress: A failed seal permits moisture and debris to enter the axle cavity, accelerating wear on the 0750117075: TAPER ROLLER BEARING and other precision components.
- Increased operating noise from the final drive: Loss of seal integrity starves the 5838300626: DIFFERENTIAL HOUSING of oil, leading to metal-on-metal contact and audible whining or grinding.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 0734.401.255 |
| Type | Rectangular Ring (Static Seal) |
| Material | Nitrile Rubber (NBR) with Fabric Reinforcement |
| Cross-Section (approx.) | 5.0 mm x 5.0 mm |
| Inside Diameter (approx.) | 255 mm |
| Operating Temperature Range | -40°C to +120°C |
| Hardness (Shore A) | 85 ± 5 |
| OEM Reference | ZF 0734.401.255 |
| Weight (approx.) | 0.08 kg |
Compatibility
This rectangular ring is a direct-fit component for ZF heavy-duty powershift transmissions commonly found in wheel loaders, graders, and dump trucks. It is specifically compatible with the following transmission models that utilize a large-diameter differential housing seal interface:
- ZF WG180 series
- ZF WG200 series
- ZF 4WG-200 series
- ZF 6WG-200 series
- ZF Ergopower (select models with 255mm seal bore)
Always verify your housing bore diameter and groove dimensions before installation. This part is frequently replaced alongside the 5838300626: DIFFERENTIAL HOUSING when performing a full axle overhaul.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 5838109012 | DIFFERENTIAL | Distributes torque between axle shafts |
| 0750117075 | TAPER ROLLER BEARING | Supports differential carrier rotation |
| 2093209023 | DIFFERENTIAL | Secondary torque distribution unit |
| 5838300626 | DIFFERENTIAL HOUSING | Encloses differential gear set |
| 0631329088 | SPRING PIN | Secures shift fork to shaft |
| 5838300811 | THRUST WASHER | Controls axial play in differential |
| 5838300721 | AXLE BEVEL GEAR | Transfers power to wheel hubs |
| 5838300633 | AXLE | Rotates to drive wheels |
| 5838300753 | THRUST WASHER | Reduces friction on gear faces |
| 5838300818 | THRUST WASHER | Prevents gear-to-housing contact |
Frequently Asked Questions
Q: Can I reuse the old rectangular ring if it looks intact?
No. This seal is a single-use component. Even if it appears undamaged, the rubber loses compression set over time. Always install a new ZF 0734.401.255 ring during any differential or housing service to guarantee a leak-free seal.
Q: What torque should I apply to the housing bolts when installing this ring?
Refer to your specific ZF transmission service manual. For most WG180/WG200 applications, housing bolts should be tightened to 85-95 Nm in a cross-pattern sequence. Over-torquing can distort the rectangular ring groove and cause immediate leakage.
Q: Does this part work with aftermarket differential housings?
This genuine OEM ring is dimensionally matched to ZF factory housings. Aftermarket housings may have different groove depths or surface finishes. We recommend using the 5838300626: DIFFERENTIAL HOUSING for guaranteed compatibility.
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Email: info@partszf.com |
Phone: +86 158 2286 3467 |
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