Overview
The ZF 0501.323.146 CUP SPRING is a precision-engineered OEM genuine component designed for the WG90 and WG94 series transmissions. This critical spring element sits within the hydraulic control assembly, providing the necessary preload force to maintain consistent pressure on valve pistons and clutch pack actuators. By ensuring proper tension, the cup spring directly influences shift quality and torque transmission stability. The SKU 0501.323.146 is manufactured to ZF’s exacting tolerances, guaranteeing a direct fit without modification. This part works in conjunction with the 4661101020: TRANSMISSION HOUSING and the 4661301046: HOUSING II to form the sealed hydraulic circuit that governs gear engagement.
Symptoms of Failure
- Delayed or harsh gear engagement: A worn cup spring loses its ability to maintain consistent hydraulic pressure, causing noticeable lag or jarring shifts when moving from neutral to drive or reverse.
- Intermittent clutch slip under load: When the spring fatigues, the clutch pack may not receive adequate clamping force, leading to momentary power loss during acceleration or uphill driving.
- Low hydraulic pressure warnings: A collapsed or cracked cup spring can cause pressure drops in the valve body, triggering dashboard alerts or diagnostic trouble codes related to line pressure.
- Oil contamination from metal debris: As the spring fractures, small metal particles can circulate through the transmission fluid, accelerating wear on adjacent components like the 0631306174: CYLINDRICAL PIN and valve bores.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | 0501.323.146 |
| OEM Reference | ZF 0501.323.146 |
| Material | Spring steel (DIN 17223), phosphate coated |
| Outer Diameter | 28.5 mm |
| Inner Diameter | 14.2 mm |
| Free Height | 6.8 mm |
| Load at Working Height | 120 N ± 10% |
| Weight | 8 grams |
| Compatible Fluid | ZF EcoFluid or Dexron III |
Compatibility
This cup spring is specifically engineered for ZF’s WG series powershift transmissions. It is a direct replacement for the following models: WG90, WG94, WG180, WG200, WG210, and WG250. The part is also used in certain variants of the WG120 and WG150 series where the hydraulic control block shares the same spring pocket dimensions. Always verify the existing spring’s free height before installation. The 4661301093: TUBE must be inspected for scoring when replacing this spring, as worn tube surfaces can accelerate spring fatigue.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4661101020 | TRANSMISSION HOUSING | Main structural casing that encloses gear sets and hydraulic circuits |
| 4661301046 | HOUSING II | Secondary housing for valve body and clutch piston assembly |
| 4661301093 | TUBE | Hydraulic fluid passage tube connecting valve body to clutch packs |
| 0631306174 | CYLINDRICAL PIN | Alignment pin for precise positioning of housing components |
| 0769123894 | TYPE PLATE | Identification plate with transmission serial number and specs |
| 0750100022 | SCREW PLUG | Sealing plug for hydraulic test ports |
| 0636302602 | SCREW PLUG | Magnetic drain plug for ferrous debris collection |
| 0634100633 | O-RING | Static seal for housing and plug interfaces |
| 4661301041 | NOZZLE | Lubrication nozzle for planetary gear sets |
| 4661301038 | NOZZLE | Cooling nozzle for clutch pack oil flow |
