Overview
The ZF 0501.209.978 HOSE PIPE is a critical fluid transfer component engineered specifically for the WG 65 Series transmission family. This OEM genuine part channels pressurized hydraulic oil between the valve body and the cooler circuit, ensuring consistent lubrication and thermal regulation within the gearbox. As a direct-fit replacement, the SKU 0501.209.978 maintains factory-specified flow rates and pressure tolerances, preventing performance degradation in heavy-duty industrial applications. When paired with the 4616105413: OUTPUT and the 4616203017: OUTPUT FLANGE, this hose pipe completes the hydraulic loop necessary for reliable torque transmission.
Symptoms of Failure
- External hydraulic oil leaks near the transmission cooler lines: A cracked or swollen 0501.209.978 hose pipe often drips ATF fluid, leaving visible puddles under the vehicle and reducing system pressure.
- Erratic gear engagement or delayed shifting: When this hose pipe fails internally, insufficient oil flow to the clutch packs causes hesitation or harsh engagement during gear changes.
- Overheating transmission with elevated fluid temperatures: A restricted or collapsed hose pipe impedes oil circulation to the cooler, leading to thermal runaway and potential damage to the 4616101117: TRANSMISSION HOUSING.
- Whining or groaning noises from the pump area: Air ingestion through a deteriorated hose pipe creates cavitation, producing audible distress signals from the hydraulic circuit.
Technical Specifications
| Part Number | 0501.209.978 |
| Product Type | Hose Pipe (Hydraulic Pressure Line) |
| Material | Reinforced synthetic rubber with textile braid |
| Inner Diameter | 12.7 mm (0.5 in) |
| Outer Diameter | 21.3 mm (0.84 in) |
| Length | Approximately 380 mm |
| Weight | 0.15 kg (0.33 lbs) |
| OEM Reference | ZF 0501.209.978 |
| Operating Pressure | Up to 18 bar (261 psi) |
| Temperature Range | -40°C to +120°C (-40°F to +248°F) |
Compatibility
This ZF hose pipe is engineered for the WG 65 Series, but its hydraulic specifications also make it suitable for adjacent ZF transmission models including the WG180, WG200, and WG250. It is a direct replacement for units equipped with external cooler lines. For proper installation, always secure the hose pipe using the 0636011038: HEXAGON SCREW to prevent vibration-induced loosening.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4616105413 | OUTPUT | Transfers rotational force from the transmission to the driveline |
| 4616203017 | OUTPUT FLANGE | Connects the output shaft to the driveshaft yoke |
| 4616101117 | TRANSMISSION HOUSING | Encloses and protects internal gear train components |
| 0636011038 | HEXAGON SCREW | Secures hose pipe brackets and mounting points |
| 0636016015 | HEXAGON SCREW | Fastens flange connections to the transmission case |
| 0631306085 | CYLINDRICAL PIN | Aligns housing halves during assembly |
| 0634313118 | O-RING | Seals hydraulic connections to prevent fluid loss |
| 0732611049 | FILTER INSERT | Removes contaminants from transmission oil |
| 0634303718 | O-RING | Provides secondary sealing for cooler line fittings |
| 0636610082 | STUD | Threaded rod for mounting transmission accessories |
