Overview
The ZF 4623.330.027 DIAPHRAGM is a critical pneumatic actuation component engineered specifically for the WG 65 Series transmission family. This OEM genuine part functions as a flexible sealing and pressure-transfer membrane within the clutch or shift actuator assembly, converting air pressure into precise mechanical movement. The SKU 4623.330.027 ensures reliable engagement and disengagement of gear sets under heavy-duty operating conditions. When installed alongside the 4616105415: OUTPUT and the 4616101094: TRANSMISSION HOUSING, this diaphragm maintains system integrity by isolating the pneumatic circuit from transmission oil.
Symptoms of Failure
When the ZF 4623.330.027 diaphragm deteriorates, operators will notice distinct performance issues. Air leaks from the actuator housing are the most common early indicator, often accompanied by a hissing sound during gear changes. Delayed or harsh shifting occurs as the diaphragm loses its ability to hold consistent pressure, causing erratic clutch modulation. Transmission oil contamination in the air system signals a ruptured diaphragm, leading to degraded shift quality and potential damage to the 4616303144: OUTPUT FLANGE. Finally, intermittent gear slipping under load points to a failing diaphragm that cannot maintain full engagement pressure.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number (SKU) | 4623.330.027 |
| Material | Nitrile rubber (NBR) with fabric reinforcement |
| Outer Diameter | 180 mm (estimated) |
| Thickness | 4.5 mm (estimated) |
| Weight | 0.12 kg (estimated) |
| OEM Reference | ZF 4623.330.027 |
| Operating Temperature Range | -40°C to +120°C |
| Burst Pressure Rating | 12 bar (174 psi) |
Compatibility
This diaphragm is primarily designed for the ZF WG 65 Series transmissions, including models such as WG65, WG80, and WG90. It also fits select WG120 and WG150 variants that share the same actuator architecture. The part is compatible with transmissions using pneumatic shift systems where the diaphragm interfaces directly with the actuator piston. Always verify the 0636011038: HEXAGON SCREW torque specifications during installation to ensure proper sealing against the housing.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4616105415 | OUTPUT | Transfers rotational force from transmission to driveline |
| 4616303144 | OUTPUT FLANGE | Connects output shaft to driveshaft with sealed interface |
| 4616101094 | TRANSMISSION HOUSING | Main structural casing enclosing all internal components |
| 0636011038 | HEXAGON SCREW | Secures actuator cover to transmission housing |
| 0636011118 | HEXAGON SCREW | Fastens output flange to output shaft |
| 0636016015 | HEXAGON SCREW | Mounts actuator assembly to transmission housing |
| 0631306085 | CYLINDRICAL PIN | Aligns actuator components during assembly |
| 0634313118 | O-RING | Seals pneumatic port on actuator housing |
| 0732611049 | FILTER INSERT | Traps debris in pneumatic supply line |
| 0634303718 | O-RING | Seals diaphragm retaining ring to actuator body |
