Overview
The ZF 4143.020.080 2 HL 270 Hydrostatic Drive Assembly is a complete, factory-sealed unit designed for demanding mobile machinery applications. This assembly functions as the primary hydraulic power transfer module within the HL 100 and HL 270 series transmissions, converting engine torque into infinitely variable hydrostatic drive. As a complete unit, SKU 4143.020.080 eliminates the need for individual component assembly, ensuring precise alignment of internal pistons and swash plates. It is typically mounted directly to the transmission housing and interfaces with the driveline via a splined output shaft. For proper installation, this unit mates with the 4143101030: HOUSING and the 4143301055: HOUSING to form a sealed hydraulic circuit.
Symptoms of Failure
When the ZF 4143.020.080 hydrostatic drive assembly begins to fail, operators typically notice these specific performance issues:
- Hydrostatic drive slipping under load: The unit loses pressure, causing the vehicle to creep or fail to maintain speed on inclines, often accompanied by whining noises from the pump.
- External oil leaks at the shaft seal: Hydraulic fluid weeping from the output shaft area, leaving puddles under the transmission after extended operation.
- Erratic forward/reverse engagement: Delayed or jerky response when shifting direction, indicating internal piston wear or swash plate binding.
- Overheating of the transmission fluid: The assembly generates excessive heat due to internal bypassing, triggering thermal warnings on the dashboard.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | 4143.020.080 |
| Series | HL 100 / HL 270 |
| Type | Hydrostatic Drive Assembly (Complete Unit) |
| Dry Weight | Approx. 18.5 kg (40.8 lbs) |
| Housing Material | High-tensile aluminum alloy |
| Max Operating Pressure | 420 bar (6,090 psi) |
| OEM Reference | ZF 2 HL 270 |
| Mounting Bolt Torque | 85 Nm (62.7 lb-ft) |
Compatibility
This hydrostatic drive assembly is engineered for the ZF HL 100 and HL 270 transmission families. It is a direct fit for models including the WG180, WG200, and WG210 series used in telehandlers, forklifts, and compact loaders. The unit also integrates with the 4143298040: CASE which houses the planetary gear set, and is secured using the 0631329135: SPRING PIN for alignment. Always verify your transmission serial number against ZF application charts before ordering.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4143101030 | HOUSING | Encloses the hydrostatic pump section |
| 4143301055 | HOUSING | Supports the motor output shaft bearings |
| 4143298040 | CASE | Contains the planetary reduction gears |
| 0631329135 | SPRING PIN | Secures the control valve linkage |
| 0501214034 | SEALING CAP | Prevents debris ingress into the port |
| 0636101024 | CAP SCREW | Fastens the housing to the transmission |
| 4475280099 | SCREW PLUG | Seals the pressure test port |
| 0634303266 | O-RING | Provides a hydraulic seal between flanges |
| 0501200072 | VENT VALVE | Relieves internal case pressure |
| 4475280015 | SCREW PLUG | Closes the drain port |
