Overview
The ZF 4644.124.406 POWER TAKE-OFF is an OEM genuine component engineered specifically for the WG 201 Series transmission family. This PTO unit transfers engine torque to auxiliary hydraulic systems, such as dump truck hoists, concrete mixer drums, or refuse packer bodies. Mounted directly to the transmission housing, it engages via a pneumatic or mechanical shift mechanism. The SKU 4644.124.406 is a direct-fit replacement that ensures factory-specified gear ratios and sealing integrity, preventing parasitic power loss in demanding vocational applications.
Symptoms of Failure
- Hydraulic system pressure drop or intermittent operation – A worn PTO gear or bearing can cause slippage under load, leading to slow or erratic auxiliary equipment performance.
- Oil seepage around the PTO mounting flange – Degraded gaskets or housing cracks allow transmission fluid to escape, often visible as drips on the bell housing or under the chassis.
- Grinding or whining noise during engagement – Damaged shift collars or worn gear teeth produce metallic sounds, particularly when the PTO is engaged without a load.
- Difficulty engaging or disengaging the PTO – A failing shift fork or seized piston can prevent smooth activation, leaving the auxiliary system stuck in an on or off state.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | 4644.124.406 |
| OEM Reference | ZF 4644.124.406 |
| Material | High-strength cast iron housing, hardened steel gears |
| Weight | Approx. 8.2 kg (18.1 lbs) |
| Mounting Flange Diameter | 130 mm |
| Output Shaft Spline | SAE B 6-tooth (standard) |
| Max Torque Capacity | 450 Nm (332 lb-ft) |
| Sealing System | Integrated O-ring and sealing ring |
Compatibility
This PTO is primarily designed for the ZF WG 201 Series, including models such as WG180, WG200, WG210, and WG211. It also fits select ZF Ecomid and ZF Ecolite transmissions with compatible SAE B PTO apertures. Always verify the transmission model and PTO opening pattern before installation. For proper sealing, pair this unit with a new 0634306198: O-RING and 0634801098: SEALING RING.
During installation, ensure the 4644101203: TRANSMISSION HOUSING or 4644301382: TRANSMISSION HOUSING is free of cracks or distortion. The 4644301189: THREADED BUSH must be torqued to specification to prevent oil bypass, and the 0636302005: SCREW PLUG should be replaced if the PTO cavity was open during service.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101203 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4644301382 | TRANSMISSION HOUSING | Alternate housing variant for WG series |
| 4644301189 | THREADED BUSH | Oil passage sealing and alignment |
| 0636302005 | SCREW PLUG | Seals unused PTO port openings |
| 0634306198 | O-RING | Static seal between PTO and housing |
| 0634801098 | SEALING RING | Dynamic shaft seal for output flange |
| 0730365067 | TYPE PLATE | Identification tag for transmission specs |
| 0631311009 | GROOVED STUD | Alignment dowel for PTO mounting |
| 4644301161 | COVER PLATE | Protects PTO aperture when not in use |
| 0636100621 | HEXAGON SCREW | Fastener for PTO flange attachment |
