Overview
The ZF 4656.006.121 is a precision-engineered OEM genuine component designed specifically for the WG 115 Series transmission. This part serves as a critical sealing and alignment element within the transmission’s hydraulic control system, ensuring consistent oil pressure and smooth gear engagement. The SKU 4656.006.121 is manufactured to ZF’s exacting tolerances, making it a direct replacement for worn units in heavy-duty industrial applications. When installed alongside the TRANSMISSION HOUSING, this component helps maintain structural integrity and prevents fluid bypass between internal galleries.
Symptoms of Failure
- Oil leaks around the transmission housing: A worn 4656.006.121 can cause hydraulic fluid to seep from the joint between the HOUS.FRONT SECT and the main casing, leading to low fluid levels and overheating.
- Erratic gear engagement or slipping: When this part degrades, internal pressure drops, causing delayed shifts or unintended neutral conditions during operation.
- Contaminated transmission fluid: A failing seal allows debris to enter the hydraulic circuit, accelerating wear on the HOUSING REAR PART and other precision components.
- Whining or grinding noises: Loss of proper sealing can introduce air into the oil, resulting in cavitation and audible distress from the gear train.
Technical Specifications
| Parameter | Value |
|---|---|
| OEM Part Number | 4656.006.121 |
| Material | High-grade nitrile rubber with steel insert |
| Outer Diameter | 68.5 mm |
| Inner Diameter | 42.0 mm |
| Thickness | 8.2 mm |
| Weight | 0.14 kg |
| Operating Temperature Range | -40°C to +120°C |
| OEM Reference | ZF 4656.006.121 (Genuine) |
Compatibility
This part is primarily engineered for the ZF WG 115 Series transmission, commonly found in municipal trucks, refuse vehicles, and medium-duty construction equipment. It is also compatible with the WG 180 and WG 200 series transmissions when used in conjunction with the correct HOUSING REAR SECTION. Always verify your transmission’s serial number before ordering, as minor design variations exist between early and late production models.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4656101056 | TRANSMISSION HOUSING | Main structural casing for gear and shaft support |
| 4656201075 | HOUS.FRONT SECT | Front section housing for pump and converter |
| 4656201077 | HOUSING REAR PART | Rear section enclosing output shaft assembly |
| 4656298049 | HOUSING REAR SECTION | Extended rear housing for PTO mounting |
| 0631306816 | CYLINDRICAL PIN | Alignment dowel for housing mating surfaces |
| 4656301148 | FIXING PLATE | Retains oil screen and prevents vibration |
| 0636100817 | CAP SCREW | M10 fastener for housing flange attachment |
| 4656301016 | SCREEN SHEET | Fine mesh filter for hydraulic return line |
| 4656301017 | SCREEN SHEET | Coarse mesh pre-filter for suction line |
| 0636100803 | CAP SCREW | M8 fastener for rear cover plate |
Frequently Asked Questions
Q: Can the 4656.006.121 be reused after transmission disassembly?
No. This is a single-use sealing component. Reusing it risks immediate leakage and pressure loss. Always replace it with a new OEM genuine part during any overhaul.
Q: How do I know if this part fits my WG 115 transmission?
Check the transmission’s data plate for the model code. The 4656.006.121 is standard on all WG 115 variants built after 2008. For earlier units, verify the housing bore diameter measures 68.5 mm.
Q: What torque should be applied to the cap screws when installing this part?
Use 45 Nm for the M10 cap screws (0636100817) and 25 Nm for the M8 cap screws (0636100803). Always use a calibrated torque wrench and apply thread locker to prevent loosening.
📞 Need this part? Contact our ZF specialists:
Email: info@partszf.com |
Phone: +86 158 2286 3467 |
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