Transfer case sealing Kit (BW4430)

Check the area where the driveshafts enter the transfer case. If you see wet residue, dark oil buildup, or “sweating” around the shaft ends, your seals are likely failing. In a BW4430 unit, these seals are the primary defense against oil loss; ignoring them can lead to internal component failure due to low lubrication.

The most common causes are heat-related hardening of the rubber, natural wear over time, or road debris getting trapped near the seal lip. When the seal loses its elasticity or gets scored, it can no longer maintain a tight grip on the rotating shaft, leading to seepage or active leaks.

While a DIYer with the right tools (like a seal puller and driver set) can do it, it requires removing the driveshafts. If you aren’t comfortable working under the vehicle or ensuring the seal is seated perfectly square, we recommend professional installation to avoid damaging the new seals during the process.

This kit is specifically designed for the BorgWarner BW4430 transfer case. This unit is commonly found in various Audi platforms. To be 100% sure, check the identification tag on your transfer case housing for the ‘BW4430’ designation before ordering.

A small leak may seem minor, but the BW4430 holds a relatively small amount of specialized fluid. If the level drops too low, the internal chain and bearings will overheat and fail, potentially costing thousands in repairs compared to the low cost of a sealing kit.