Overview
The ZF 4651.306.108 COVER PLATE is a critical sealing and structural component designed exclusively for the WG 100 series transmission family. This OEM genuine part, identified by SKU 4651.306.108, mounts directly to the rear section of the transmission housing, providing a secure barrier that contains hydraulic fluid and protects internal clutch packs from external contaminants. It interfaces precisely with the TRANSMISSION HOUSING (4651101009) and the HOUSING (4651301025) to maintain proper oil circulation and structural integrity under high torque loads.
Symptoms of Failure
- External oil seepage around the rear bell housing: When the cover plate gasket surface degrades, transmission fluid escapes, leaving visible drips or wet spots on the underside of the vehicle.
- Erratic gear engagement or delayed shifting: A warped or cracked cover plate disrupts internal hydraulic pressure, causing hesitation when shifting between forward and reverse gears.
- Increased operating noise or vibration: Loose fasteners or a fatigued plate allow the assembly to flex, producing a distinct rattle or hum during acceleration.
- Contaminated transmission fluid: A compromised seal permits dirt and moisture to enter through the plate interface, leading to premature wear of internal components.
Technical Specifications
| Part Number | 4651.306.108 |
| Material | Die-cast aluminum alloy with corrosion-resistant coating |
| Overall Dimensions | 320 mm x 180 mm x 12 mm |
| Weight | 1.45 kg (3.2 lbs) |
| OEM Reference | ZF 4651.306.108 |
| Bolt Hole Pattern | 8 x M10 threaded holes on 280 mm centers |
| Sealing Surface | Precision machined flatness tolerance ±0.05 mm |
Compatibility
This cover plate is engineered for the ZF WG 100 series, but it also fits select models in the WG 180 and WG 200 families where the rear housing geometry matches. It is commonly used in WG 100, WG 120, and WG 150 transmissions found in medium-duty trucks and industrial equipment. For proper installation, pair this plate with a new O-RING (0634303928) and verify alignment with the HOUSING (4651301031) to prevent fluid bypass.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4651101009 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4651301025 | HOUSING | Intermediate support for clutch assembly |
| 0634303928 | O-RING | Seals cover plate to housing interface |
| 4651301031 | HOUSING | Rear section housing for output shaft |
| 4651203002 | SCREEN SHEET | Filters debris from hydraulic fluid |
| 4651303005 | SCREEN SHEET | Secondary filtration element |
| 0636101032 | CAP SCREW | Fastens cover plate to housing |
| 0630361028 | SEALING CAP | Protects unused port openings |
| 4475280060 | SCREW PLUG | Seals drain or fill ports |
| 0634303312 | O-RING | Seals screw plug to housing |
