Overview
The ZF 0634.303.110 O-RING is a precision-engineered sealing component designed for use in ZF WG181, WG250, and WG258 transmissions. This OEM genuine part creates a critical fluid-tight barrier between mating surfaces within the transmission housing, preventing oil migration and maintaining hydraulic pressure integrity. The SKU 0634.303.110 is specifically positioned in the valve body and clutch piston assemblies, where it isolates high-pressure circuits from low-pressure sump areas. When installed correctly, this O-ring ensures consistent lubrication flow to planetary gear sets and torque converter components. For complete assembly integrity, this O-ring works in conjunction with the 4644101047 TRANSMISSION HOUSING and the 4644301380 HOUSING to form a leak-proof system.
Symptoms of Failure
- External transmission oil leaks at housing mating surfaces: When the 0634.303.110 O-ring hardens or cracks, pressurized ATF seeps past the seal, leaving visible drips or wet spots on the transmission case exterior.
- Erratic gear engagement or delayed shifting: A degraded O-ring causes internal pressure loss, resulting in sluggish clutch pack application and harsh shift transitions during acceleration.
- Low transmission fluid level without visible external leaks: Internal cross-leakage through a failed O-ring allows fluid to bypass into the torque converter housing, causing sump starvation and potential overheating.
- Whining or buzzing noise from transmission pump: Air ingestion through a compromised O-ring creates cavitation in the hydraulic circuit, producing audible pump distress under load.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number (SKU) | 0634.303.110 |
| Material | Nitrile Rubber (NBR) / FKM (Viton) estimated |
| Inner Diameter | ~18.0 mm |
| Cross-Section Thickness | ~2.5 mm |
| Weight | ~2 grams |
| OEM Reference | ZF 0634.303.110 |
| Temperature Range | -40°C to +120°C |
| Hardness (Shore A) | 70 ±5 |
Compatibility
This O-ring is engineered for ZF WG-series powershift transmissions. Verified compatible models include: WG 181 Series, WG 250 Series, WG 251 Series, WG 258 Series, WG 260 Series, WG 261 Series, WG 308 Series, and WG 311 Series. It is also suitable for WG180 and WG200 variants where the same sealing groove geometry is used. For proper installation, ensure the 4644301189 THREADED BUSH is torqued to specification and the 0730365067 TYPE PLATE is correctly aligned to avoid O-ring pinching.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101047 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4644301380 | HOUSING | Secondary housing for valve body assembly |
| 4644301189 | THREADED BUSH | Provides threaded anchor for housing bolts |
| 0730365067 | TYPE PLATE | Identification plate with transmission specs |
| 0631311009 | GROOVED STUD | Alignment dowel for housing positioning |
| 4644301161 | COVER PLATE | Seals access port to clutch pack |
| 0636100621 | HEXAGON SCREW | Fastener for cover plate retention |
| 0631610020 | SET SCREW | Adjustable stop for shift mechanism |
| 0634801098 | SEALING RING | Static seal for drain plug bore |
| 4644301117 | FIXING PLATE | Retains valve body to housing |
ZF 0634.303.110 O形圈 – O-Ring RFQ Support
PartsZF helps B2B buyers source ZF 0634.303.110 O形圈 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 0634.303.110 when sending your RFQ. PartsZF can review dotted, spaced, and compact number formats against the available product and documentation records.
Application Context
- Documentation reference: 4646086048
- Documentation reference: 4646044025
- Documentation reference: 4646004074
- Documentation reference: 4646004075
- Illustration section: SPUR GEAR DRIVE
- Illustration section: COUPLING
- Illustration section: CLUTCH
Cross Reference Support
- Cross-reference record available for RFQ review.
Specification Snapshot
| ZF part number | 0634.303.110 |
|---|---|
| Normalized SKU | 0634303110 |
| Part name | O形圈 |
| Product category | O-ring |
| Cross-reference support | Available for RFQ review |
| Weight | 0.006 |
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.
Related Parts
- ZF 0634.303.280 O-RING
- ZF 0634.306.523 O-RING
- ZF 0634.306.213 O-RING
- ZF 0734.313.134 O-RING
- ZF 0634.313.728 O-RING

