Overview
The ZF 4143.000.187 2 HL 100 Hydrostatic Drive Assembly is a complete, pre-assembled unit engineered for precise power delivery in heavy-duty industrial transmissions. This core component converts hydraulic pressure into mechanical torque, enabling smooth, variable-speed operation in ZF HL 100 and HL 270 series gearboxes. As a fully sealed assembly, the SKU 4143.000.187 eliminates the need for field assembly of internal pistons and swashplates, reducing installation downtime. It integrates directly with the transmission housing, where it interfaces with the 4143101014: HOUSING and the 4143301025: HOUSING to form a leak-proof hydraulic circuit. This unit is a direct OEM replacement, ensuring original performance specifications are maintained.
Symptoms of Failure
- Hydrostatic drive slipping under load: When the assembly wears, internal piston seals degrade, causing pressure loss and erratic torque output during heavy operation.
- External oil leaks at the drive flange: Deteriorated sealing surfaces or a compromised 0634313603: O-RING allow hydraulic fluid to weep from the unit, leaving visible puddles under the transmission.
- Excessive whining or grinding noise: Worn bearings or scored cylinder blocks produce a high-pitched noise that intensifies with speed, indicating imminent failure.
- Erratic speed control or jerky starts: A failing hydrostatic assembly cannot maintain consistent flow, leading to sudden lurches or hesitation when engaging the drive.
Technical Specifications
| Parameter | Value |
|---|---|
| OEM Part Number | 4143.000.187 |
| Assembly Type | 2 HL 100 Hydrostatic Drive (Complete Unit) |
| Maximum Operating Pressure | 420 bar (6,090 psi) |
| Displacement | 100 cm³/rev |
| Housing Material | High-tensile cast iron |
| Dry Weight | 34.5 kg (76.1 lbs) |
| Seal Material | Nitrile rubber (NBR) |
| Mounting Bolt Torque | 120 Nm (88.5 lb-ft) |
| OEM Reference | ZF Friedrichshafen AG |
Compatibility
This hydrostatic drive assembly is specifically designed for ZF HL 100 and HL 270 series transmissions. It is a direct fit for models including the WG180, WG200, and WG250 gearboxes commonly used in wheel loaders, forklifts, and industrial tractors. The unit also serves as a replacement in certain WG150 and WG300 configurations where the HL 100 pump module is specified. Always verify the existing transmission model and serial number against the 4143.000.187 part number before ordering. For proper installation, ensure the 4475280018: SCREW PLUG is torqued to specification to prevent pressure loss.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4143101014 | HOUSING | Encloses the hydrostatic drive assembly |
| 4143301025 | HOUSING | Secondary housing for valve block integration |
| 0634313603 | O-RING | Seals the drive flange to prevent leaks |
| 4475280018 | SCREW PLUG | Closes hydraulic ports during service |
| 0501342341 | SUPPORT RING | Reinforces O-ring grooves under high pressure |
| 4143298457 | SEAL KIT | Complete set of seals for overhaul |
| 0634313591 | O-RING | Seals the suction port connection |
| 0636101068 | CAP SCREW | Fastens the assembly to the transmission |
| 4143221014 | THROTTLE VALVE | Controls hydraulic flow rate |
| 0634313164 | O-RING | Seals the throttle valve housing |
