Overview
The ZF 4660.303.028 OUTPUT FLANGE is a critical driveline component engineered specifically for the WG 98 series transmission family. This OEM genuine part serves as the primary interface between the transmission output shaft and the driveshaft, transferring rotational torque from the gearbox to the vehicle’s differential. Machined from high-strength alloy steel, the flange ensures precise alignment and vibration-free power delivery under heavy loads. The SKU 4660.303.028 is designed to bolt directly onto the output shaft, with a splined bore that matches the WG98’s internal gearing. For optimal assembly integrity, this flange is often installed alongside the 4660101006: TRANSMISSION HOUSING and the 4660301014: HOUSING II, which provide structural support and sealing for the output area.
Symptoms of Failure
- Oil seepage at the output shaft seal: A worn or cracked output flange allows transmission fluid to escape past the seal, leaving puddles under the vehicle and reducing lubrication levels.
- Driveline vibration during acceleration: When the flange’s splines wear or the mating surface becomes distorted, it creates imbalance that transmits through the driveshaft as a low-frequency shudder.
- Clunking noise when shifting between drive and reverse: Excessive backlash in the flange-to-shaft connection produces a metallic knock as torque direction changes.
- Difficulty maintaining gear engagement: A loose output flange can cause the output shaft to shift axially, leading to intermittent slipping or delayed engagement in the WG98 transmission.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number (SKU) | 4660.303.028 |
| Material | High-tensile alloy steel (C45E / 1.1191 equivalent) |
| Overall Diameter | 180 mm (7.09 in) |
| Flange Thickness | 28 mm (1.10 in) |
| Spline Count | 24 internal splines (SAE standard) |
| Weight | 2.8 kg (6.17 lbs) |
| OEM Reference | ZF 4660.303.028 |
| Surface Treatment | Zinc-plated with black passivation |
Compatibility
This output flange is primarily designed for the ZF WG 98 series, but its spline pattern and bolt circle also make it compatible with the following ZF transmission models: WG180, WG200, and WG210. It is a direct replacement for earlier WG98 variants and can be retrofitted to certain WG150 units with a matching output shaft. Always verify the spline count and pilot bore diameter before installation. For complete transmission rebuilds, consider pairing this flange with the 0631306174: CYLINDRICAL PIN for precise alignment and the 0769123894: TYPE PLATE for correct identification of your unit.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4660101006 | TRANSMISSION HOUSING | Main structural casing for the gearset |
| 4660301014 | HOUSING II | Rear housing section supporting output shaft |
| 0631306174 | CYLINDRICAL PIN | Alignment dowel for housing mating |
| 0769123894 | TYPE PLATE | Identification tag for transmission model |
| 0750100022 | SCREW PLUG | Seals oil drain or fill ports |
| 4660221013 | TUBE | Oil delivery conduit inside housing |
| 0634100317 | O-RING | Static seal for flange-to-housing joint |
| 0636103273 | CAP SCREW | Fastener for flange retention |
| 0634306311 | O-RING | Secondary seal for output shaft area |
| 4660321029 | FIXING PLATE | Locks flange nut to prevent loosening |
