Overview
The ZF 4143.352.051 PISTON is a critical hydraulic actuation component engineered for the HL 100 and HL 270 transmission series. This OEM genuine part converts hydraulic pressure into precise mechanical force to engage clutch packs and shift gears within the valve body assembly. The SKU 4143.352.051 sits directly inside the 4143101022: HOUSING, where it seals against high-pressure oil circuits. When combined with the 4143301044: HOUSING, this piston ensures smooth, repeatable gear engagement under heavy industrial loads.
Symptoms of Failure
- Erratic gear engagement or delayed shifting — A worn piston cannot maintain consistent hydraulic pressure, causing hesitation when the transmission shifts from neutral to drive.
- Internal hydraulic oil leaks — Cracks or scoring on the piston surface allow pressurized oil to bypass, leading to low system pressure and visible drips near the valve body.
- Transmission slipping under load — When the piston fails to fully stroke, clutch packs do not lock completely, resulting in power loss during acceleration or uphill operation.
- Abnormal noise from the transmission sump — A loose or broken piston can rattle inside the housing, producing a metallic tapping sound that worsens with RPM changes.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number | 4143.352.051 |
| Material | Hardened alloy steel with anti-corrosion coating |
| Outer Diameter | 52 mm (approx.) |
| Height | 35 mm (approx.) |
| Weight | 0.18 kg |
| OEM Reference | ZF 4143.352.051 |
| Seal Type | Compatible with 0634801057: SEALING RING |
Compatibility
This piston is designed for ZF HL 100 and HL 270 series transmissions, which are widely used in wheel loaders, forklifts, and heavy-duty material handling equipment. It also fits select WG180 and WG200 models that share the same hydraulic control architecture. For proper installation, always pair this piston with a new 0631329135: SPRING PIN and verify the 0636302014: SCREW PLUG torque specifications. Additional compatible components include the 4143301053: CONNECTING PART and 0636100600: CAP SCREW.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4143101022 | HOUSING | Encloses piston assembly |
| 4143301044 | HOUSING | Secondary housing for valve body |
| 0631329135 | SPRING PIN | Secures piston to linkage |
| 0636302014 | SCREW PLUG | Seals hydraulic port |
| 0634801057 | SEALING RING | Prevents oil bypass |
| 4143301053 | CONNECTING PART | Links piston to shift fork |
| 0636100600 | CAP SCREW | Fastens housing assembly |
| 0636101024 | CAP SCREW | Alternate fastener for valve body |
| 0730365159 | TYPE PLATE | Identification label for transmission |
| 0631311009 | GROOVED STUD | Alignment pin for housing |





