Overview
The ZF 4644.199.968 LOOSE PARTS for WG200 is a critical service kit designed to restore the internal integrity of your ZF WG200 series transmission. This OEM genuine assembly contains the essential loose components—including seals, retainers, and small hardware—that secure the hydraulic circuit and rotating assemblies within the gearbox. Specifically, this part number (SKU: 4644.199.968) replaces the individual fasteners and spacers that can loosen over time due to thermal cycling and vibration. When installed alongside the 4644105423: DISCONNECTION unit and the 4644303054: OUTPUT FLANGE, this kit ensures that the main shaft assembly remains properly torqued and aligned within the 4644101232: TRANSMISSION HOUSING.
Symptoms of Failure
When the ZF 4644.199.968 LOOSE PARTS begin to degrade, operators will notice distinct performance issues. Look for these specific failure symptoms:
- Oil seepage at the bell housing joint: Worn loose parts allow hydraulic fluid to bypass the seal interface, leading to visible drips under the transmission.
- Intermittent gear slipping under load: Loose retainers cause the clutch pack clearance to shift, resulting in momentary loss of torque during acceleration.
- Abnormal rattling from the transmission housing: Unsecured components vibrate against the 0636021010: HEXAGON SCREW points, creating a metallic chatter at idle.
- Delayed engagement when shifting from neutral to drive: Worn spacers reduce hydraulic pressure buildup, causing a 2–3 second lag before the gear engages.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number | 4644.199.968 |
| Material | Case-hardened steel with zinc-nickel plating |
| Weight (kit) | 0.85 kg (1.87 lbs) |
| OEM Reference | ZF 4644.199.968 |
| Thread Size (primary) | M10 x 1.5 |
| Torque Specification | 45 Nm ± 5 Nm |
| Operating Temperature Range | -40°C to +120°C |
Compatibility
This LOOSE PARTS kit is engineered primarily for the ZF WG200 series transmissions used in medium-duty trucks, buses, and off-highway equipment. Based on the part type and fastener geometry, it is also compatible with the ZF WG180 and ZF WG150 models that share the same bell housing bolt pattern. Always verify the serial number of your transmission before installation. For complete assembly, this kit works in concert with the 4644301282: TRANSMISSION HOUSING and the 4475280043: SCREW PLUG to seal the main case.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644105423 | DISCONNECTION | Isolates the torque converter from the driveline during shifts |
| 4644303054 | OUTPUT FLANGE | Connects the transmission output shaft to the driveshaft |
| 0636021010 | HEXAGON SCREW | Secures the loose parts kit to the housing |
| 4644101232 | TRANSMISSION HOUSING | Main structural casing for the gear train |
| 4644301282 | TRANSMISSION HOUSING | Alternate housing variant for WG200 series |
| 4475280043 | SCREW PLUG | Seals oil passages in the housing |
| 0634306198 | O-RING | Provides a static seal between mating surfaces |
| 0730365067 | TYPE PLATE | Identification label for transmission model |
| 4644301298 | COVER PLATE | Protects the shift mechanism from debris |
| 4644106300 | SHIFT SYSTEM | Controls gear selection via hydraulic valves |
