Overview
The ZF 4644.301.379 COVER PLATE is a critical sealing and protective component designed for the WG 201 series of heavy-duty automatic transmissions. This OEM genuine part sits on the exterior of the transmission housing, serving as a barrier that prevents fluid contamination and maintains internal pressure integrity. Specifically, the SKU 4644.301.379 mounts directly to the main casing, covering access points for internal valve bodies and clutch assemblies. By securing the transmission’s internal environment, this cover plate ensures consistent hydraulic function and extends the service life of adjacent components such as the 4644101160 TRANSMISSION HOUSING and the 4644301323 TRANSMISSION HOUSING.
Symptoms of Failure
When the ZF 4644.301.379 cover plate deteriorates, operators may notice several distinct failure indicators. Oil leaks around the transmission casing are the most common symptom, often appearing as drips or wet spots near the cover plate seam. Another sign is gear slipping or delayed engagement, caused by a loss of hydraulic pressure when the seal is compromised. Contaminated transmission fluid—visible as dark or gritty oil—can result from debris entering through a cracked or warped plate. Finally, unusual whining or grinding noises during gear shifts may indicate that the cover plate has loosened, allowing internal components to shift out of alignment.
Technical Specifications
| Specification | Detail |
|---|---|
| Part Number | 4644.301.379 |
| Material | Die-cast aluminum alloy with corrosion-resistant coating |
| Dimensions (L x W x H) | 210 mm x 145 mm x 8 mm |
| Weight | 0.85 kg (1.87 lbs) |
| OEM Reference | ZF Friedrichshafen AG |
| Surface Finish | Machined mating face with anodized protection |
| Bolt Hole Pattern | 6 x M8 threaded holes on 180 mm centers |
Compatibility
This cover plate is engineered primarily for the ZF WG 201 series transmissions, which are widely used in municipal buses, fire trucks, and heavy construction vehicles. It is also compatible with the WG 180 and WG 200 models, as these share the same housing interface dimensions. For proper installation, ensure the mating surface on the 4644301189 THREADED BUSH is clean, and secure the plate using the 4475280043 SCREW PLUG to seal any auxiliary ports. Always verify compatibility with your specific transmission serial number before ordering.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101160 | TRANSMISSION HOUSING | Main structural casing for gear and clutch assemblies |
| 4644301323 | TRANSMISSION HOUSING | Secondary housing section for torque converter area |
| 4644301189 | THREADED BUSH | Reinforced insert for bolt mounting points |
| 4475280043 | SCREW PLUG | Seals oil passages and pressure test ports |
| 0634306198 | O-RING | Provides leak-proof seal between cover and housing |
| 0730365067 | TYPE PLATE | Identification tag with transmission model and serial number |
| 4644301161 | COVER PLATE | Alternate cover variant for different port configurations |
| 0636100621 | HEXAGON SCREW | Fastener for securing cover plate to housing |
| 0631610020 | SET SCREW | Adjustable locking screw for alignment |
| 0501218540 | BREATHER | Vents internal pressure while blocking contaminants |
