Overview
The ZF 4143.020.252 2 HL 290 Hydrostatic Drive Assembly is a complete, high-precision unit engineered for demanding industrial drivetrain applications. This assembly serves as the core hydraulic power transfer component within ZF’s HL 100 and HL 270 series transmissions, converting engine torque into smooth, variable-speed output for wheeled loaders, telehandlers, and heavy construction machinery. The SKU 4143.020.252 integrates seamlessly with the transmission housing, ensuring reliable hydrostatic braking and forward/reverse modulation. For optimal assembly integrity, this unit is designed to be paired with the 4143101046 HOUSING and the 4143301055 HOUSING, which provide structural support and fluid channeling.
Symptoms of Failure
- Hydrostatic drive slipping under load: When the assembly wears, you may notice a loss of traction or delayed response when accelerating, particularly on inclines or under heavy bucket loads.
- External oil leaks from the drive housing: Degraded seals or a cracked 4143298040 CASE can cause hydraulic fluid to weep around the unit, leading to low oil levels and overheating.
- Erratic or jerky directional changes: Worn internal pistons or a failing swashplate can cause sudden lurching when shifting from forward to reverse, indicating the need for immediate replacement.
- Excessive noise during operation: A whining or grinding sound from the transmission area often signals bearing wear or cavitation within the hydrostatic loop.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | 4143.020.252 |
| Assembly Type | 2 HL 290 Hydrostatic Drive (Complete Unit) |
| OEM Reference | ZF 2 HL 290 |
| Material | High-tensile cast iron housing with hardened steel internals |
| Weight | Approx. 48 kg (106 lbs) |
| Dimensions (L x W x H) | 420 mm x 310 mm x 280 mm |
| Max Operating Pressure | 420 bar (6,090 psi) |
| Fluid Capacity | 2.8 liters (0.74 gal) |
Compatibility
This hydrostatic drive assembly is primarily designed for ZF transmission models in the HL 100 and HL 270 series. It is a direct fit for the ZF WG180, WG200, and WG210 transmissions commonly found in compact wheel loaders and telescopic handlers. The unit also retrofits into certain ZF 2 HL 250 and 2 HL 290 driveline configurations. Always verify your transmission model and serial number before ordering. For a complete rebuild, consider replacing the 0631329135 SPRING PIN which secures the control linkage inside the assembly.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4143101046 | HOUSING | Main structural enclosure for the drive unit |
| 4143301055 | HOUSING | Secondary housing for bearing support |
| 4143298040 | CASE | Protective casing for internal gears |
| 0631329135 | SPRING PIN | Locks actuator linkage to swashplate |
| 0501214034 | SEALING CAP | Prevents fluid ingress at ports |
| 0636101024 | CAP SCREW | Secures housing halves together |
| 4475280099 | SCREW PLUG | Seals test ports and drain holes |
| 0634303266 | O-RING | Hydraulic seal between mating surfaces |
| 0501200072 | VENT VALVE | Relieves internal pressure buildup |
| 0501217673 | LUBRICATING NIPPLE | Grease point for bearing maintenance |
