Overview
The ZF 0634.402.500 R-RING is a precision-engineered sealing component designed for the WG100, WG191, and WG211 series transmissions. This OEM genuine part functions as a critical static seal between the transmission housing and the internal hydraulic circuit, preventing fluid migration and maintaining system pressure. The SKU 0634.402.500 sits specifically at the interface where the TRANSMISSION HOUSING meets the HOUSING assembly, ensuring a leak-proof seal under high thermal and pressure cycles. As an OEM genuine component, it meets ZF’s exacting tolerances for material hardness and dimensional stability, directly influencing transmission longevity and operational reliability.
Symptoms of Failure
- External oil seepage at housing joint: When the 0634.402.500 R-RING degrades, you may notice wet spots or drips around the mating surface between the HOUSING and the main casing, often mistaken for a gasket failure.
- Intermittent gear slipping under load: A worn R-RING can cause internal pressure loss, leading to delayed clutch engagement or erratic shifting, particularly in WG191 models operating at high torque.
- Hydraulic fluid contamination: Cracking or hardening of the ring material allows debris ingress, accelerating wear on adjacent components like the O-RING seals and valve bodies.
- Increased operating temperature: A compromised seal reduces lubrication efficiency, causing localized overheating detectable via transmission fluid analysis.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 0634.402.500 |
| Material | Nitrile Rubber (NBR) with PTFE coating |
| Inner Diameter | 102.5 mm |
| Outer Diameter | 115.8 mm |
| Cross-Section | 3.5 mm |
| Weight | 0.018 kg |
| OEM Reference | ZF 0634.402.500 |
| Temperature Range | -40°C to +120°C |
Compatibility
This R-RING is engineered for ZF WG-series transmissions, specifically the WG100, WG191, and WG211 models. It is also compatible with WG180, WG200, and WG250 variants where the housing interface uses the same sealing groove geometry. The part integrates directly with the TRANSMISSION HOUSING (part 4651101006) and the HOUSING (part 4651301034) assemblies. For complete seal replacement, pair this R-RING with the O-RING (0634303928) and the HOUSING (4651301013) for optimal sealing integrity across all WG-series platforms.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4651101006 | TRANSMISSION HOUSING | Main structural casing for gear assembly |
| 4651301034 | HOUSING | Intermediate housing for valve body integration |
| 0634303928 | O-RING | Static seal for hydraulic port connections |
| 4651301013 | HOUSING | Rear housing for output shaft support |
| 4651301015 | SCREEN SHEET | Filtration mesh for hydraulic fluid |
| 4651301035 | SCREEN SHEET | Secondary filtration element |
| 0630361028 | SEALING CAP | Closure for pressure test ports |
| 4475280060 | SCREW PLUG | Threaded plug for drain or fill holes |
| 0634303312 | O-RING | Seal for screw plug applications |
| 0630361063 | SEALING CAP | High-temperature cap for sensor ports |
Frequently Asked Questions
Q: How do I know if the 0634.402.500 R-RING needs replacement?
A: Inspect for visible cracking, flattening, or hardening of the rubber. If you observe oil weeping from the housing joint after a pressure test, replace the ring immediately to avoid internal pressure loss.
Q: Can I reuse this R-RING after disassembly?
A: No. ZF recommends always installing a new OEM 0634.402.500 R-RING whenever the housing is separated, as the material takes a compression set and loses sealing effectiveness upon reinstallation.
Q: Is this part compatible with synthetic transmission fluids?
A: Yes, the NBR/PTFE compound is fully compatible with mineral-based and synthetic ATF fluids used in WG100 and WG191 transmissions, including Dexron III and ZF LifeguardFluid 8.
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Email: info@partszf.com |
Phone: +86 158 2286 3467 |
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ZF 0634.402.500 R-RING – O-Ring RFQ Support
PartsZF helps B2B buyers source ZF 0634.402.500 R-RING with fast RFQ support, expert part-number lookup, documentation review, and export coordination. This O-ring page is built from confirmed catalog, media, and reference data to reduce sourcing uncertainty for construction machinery transmission parts.
Part-Number Summary
Use ZF number 0634.402.500 when sending your RFQ. PartsZF can review dotted, spaced, and compact number formats against the available product and documentation records.
Application Context
- Documentation reference: 4657033001
- Documentation reference: 4657033002
- Documentation reference: 4657033003
- Documentation reference: 4657033005
- Illustration section: COUPLING
- Illustration section: CLUTCH
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 | 0634.402.500 |
|---|---|
| Normalized SKU | 0634402500 |
| Part name | R-RING |
| Product category | O-ring |
| Cross-reference support | Available for RFQ review |
| Weight | 0.009 |
Image and Documentation Notes
Current product media status: diagram. 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.
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