Overview
The ZF 4143.351.037 PISTON is a critical hydraulic actuation component engineered for the HL 100 and HL 270 series transmissions. This OEM genuine part converts hydraulic pressure into mechanical force to engage clutch packs and shift gears within the transmission valve body. The SKU 4143.351.037 sits directly inside the piston housing assembly, where it must maintain a precise seal to ensure consistent line pressure. When installed alongside the 4143101016 HOUSING and the 4143301039 HOUSING, this piston forms the core of the shift actuation system. Proper sealing is achieved using the 0501318136 GASKET and secured with the 0636101084 CAP SCREW.
Symptoms of Failure
- Erratic gear engagement or delayed shifting: A worn piston cannot maintain hydraulic pressure, causing hesitation when the transmission shifts between forward and reverse gears.
- Internal hydraulic fluid leaks: Damaged piston seals allow oil to bypass the piston, leading to visible drips from the bell housing or valve body area.
- Clutch pack slippage under load: Insufficient piston stroke reduces clamping force on clutch discs, resulting in RPM flare during acceleration.
- Transmission overheating: Continuous slippage from a failing piston generates excess heat, often triggering thermal warning lights on heavy equipment.
Technical Specifications
| Specification | Detail |
|---|---|
| Part Number | 4143.351.037 |
| Material | Hardened alloy steel with nitrided surface |
| Outer Diameter | 85 mm (estimated) |
| Inner Diameter | 32 mm (estimated) |
| Height | 45 mm (estimated) |
| Weight | 0.85 kg (estimated) |
| OEM Reference | ZF 4143.351.037 |
| Seal Type | Integrated PTFE lip seal |
Compatibility
This piston is specifically designed for ZF HL 100 and HL 270 series transmissions. It is also compatible with the following ZF models that share the same hydraulic architecture: WG180, WG200, 4WG180, and 4WG200. Always verify piston bore condition and inspect the 0634306198 O-RING during replacement to prevent cross-threading.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4143101016 | HOUSING | Encloses piston assembly |
| 4143301039 | HOUSING | Secondary housing for valve body |
| 0501318136 | GASKET | Seals housing mating surfaces |
| 0636101084 | CAP SCREW | Secures piston assembly |
| 0750108044 | PLUG | Closes hydraulic ports |
| 0636302014 | SCREW PLUG | Threaded port seal |
| 0634801057 | SEALING RING | Prevents fluid bypass |
| 0730365092 | TYPE PLATE | Identification label |
| 4143201019 | VALVE INSERT | Controls hydraulic flow |
| 0634306198 | O-RING | Seals piston bore |
Authorized ZF Distributor
We are a certified supplier of genuine ZF components.





