Overview
The ZF 0732.040.855 COMPRESSION SPRING is a critical OEM genuine component engineered specifically for the WG 100 and WG 201 series transmissions. This precision spring sits within the valve body assembly, where it provides the necessary tension to control hydraulic pressure regulation and clutch pack engagement. As an original ZF part, the SKU 0732.040.855 ensures exact spring rate and fatigue resistance required for consistent shift quality. When installed alongside the 4644101160: TRANSMISSION HOUSING, this compression spring maintains proper alignment and load distribution within the hydraulic control circuit.
Symptoms of Failure
- Delayed or harsh shifting: A worn compression spring loses its calibrated tension, causing erratic clutch application and noticeable shift shock during gear changes.
- Intermittent gear slipping under load: When the spring fatigues, hydraulic pressure drops in specific circuits, leading to momentary loss of torque transfer during acceleration.
- Erratic pressure regulator behavior: A broken or collapsed spring can cause fluctuating line pressure, resulting in inconsistent transmission response and potential overheating.
- Audible clicking or rattling from valve body: If the spring fractures, loose fragments may produce metallic noises inside the transmission pan, often accompanied by debris in the fluid.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number (SKU) | 0732.040.855 |
| Material | Chrome-silicon alloy steel (DIN 17223) |
| Wire Diameter | 2.5 mm |
| Outer Diameter | 18.0 mm |
| Free Length | 45.0 mm |
| Spring Rate | 12.5 N/mm |
| Weight | 0.012 kg |
| OEM Reference | ZF 0732.040.855 |
| Surface Treatment | Phosphate coated (anti-corrosion) |
Compatibility
This compression spring is designed for ZF WG series transmissions, specifically the WG 100 and WG 201 models. It is also compatible with the WG180, WG200, and WG210 variants where the valve body uses identical spring dimensions. For proper installation, ensure the 4644301323: TRANSMISSION HOUSING is free of wear or scoring that could affect spring seating. Additionally, the 4644301189: THREADED BUSH and 4475280043: SCREW PLUG should be inspected during service to prevent fluid bypass.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101160 | TRANSMISSION HOUSING | Main structural casing for gear and valve body assembly |
| 4644301323 | TRANSMISSION HOUSING | Rear housing section supporting output shaft |
| 4644301189 | THREADED BUSH | Wear-resistant insert for hydraulic port sealing |
| 4475280043 | SCREW PLUG | Sealing plug for oil gallery access points |
| 0634306198 | O-RING | Elastomeric seal for fluid containment |
| 0730365067 | TYPE PLATE | Identification tag with transmission serial number |
| 4644301161 | COVER PLATE | Protective cover for valve body access |
| 0636100621 | HEXAGON SCREW | Fastener for housing and cover plate mounting |
| 0631610020 | SET SCREW | Adjustment screw for pressure regulator calibration |
| 0501218540 | BREATHER | Ventilation valve to equalize internal pressure |
