Overview
The ZF 4644.183.185 LOOSE PARTS for WG200 is a critical internal component set designed to maintain precise hydraulic and mechanical clearances within the WG200 series transmission. This OEM genuine part, identified by SKU 4644.183.185, functions as a retention and sealing assembly that secures the clutch pack and valve body alignment. When installed correctly, it prevents axial movement of the rotating elements, ensuring consistent oil pressure distribution across the gear train. This part is typically located in the intermediate housing section, directly interfacing with the TRANSMISSION HOUSING and the TRANSMISSION HOUSING to create a sealed operating environment.
Symptoms of Failure
- Intermittent gear slippage under load: When the 4644.183.185 LOOSE PARTS lose their dimensional integrity, the clutch pack clearance increases, causing the transmission to slip during acceleration or hill climbing.
- Hydraulic fluid seepage from the bell housing: Worn components in this set compromise the seal between the COVER PLATE and the main casing, leading to visible oil drips after extended operation.
- Delayed engagement when shifting from Neutral to Drive: A failing loose parts set reduces the preload on the shift valves, resulting in a 2-3 second hesitation before gear engagement.
- Abnormal metallic rattling at low RPM: As the parts degrade, the loose fit allows the internal snap rings and spacers to vibrate against the housing, producing a distinct chatter sound.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | 4644.183.185 |
| Material Composition | Hardened Steel (DIN 1.3505) with Nitrile Coating |
| Outer Diameter | 185 mm |
| Inner Diameter | 120 mm |
| Thickness | 12.5 mm |
| Weight | 0.85 kg |
| OEM Reference | ZF 4644.183.185 |
| Operating Temperature Range | -40°C to +120°C |
| Torque Capacity | 450 Nm |
Compatibility
This OEM genuine part is specifically engineered for the ZF WG200 series transmissions, including the WG200, WG180, and WG160 variants. It is also compatible with select ZF Ecomat 4HP and 5HP models that share the same intermediate housing architecture. The 4644.183.185 LOOSE PARTS set is not interchangeable with the WG210 series due to different spline counts. For proper installation, always verify the TYPE PLATE on your transmission to confirm the exact model designation.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101275 | TRANSMISSION HOUSING | Main structural casing for gear assembly |
| 4644301406 | TRANSMISSION HOUSING | Secondary housing for valve body integration |
| 0730301612 | TYPE PLATE | Identification plate with transmission specs |
| 4644301298 | COVER PLATE | Sealing cover for access port |
| 0634306323 | O-RING | Hydraulic seal for pressure lines |
| 0636305026 | SCREW PLUG | Threaded plug for drain/fill ports |
| 4644301279 | SCREEN SHEET | Filter mesh for oil debris |
| 4644301088 | SEALING CAP | Protective cap for sensor ports |
| 4644106328 | SHIFT SYSTEM | Valve body assembly for gear selection |
| 4644109046 | PARKING BRAKE | Mechanical lock for parked position |
