Transfer case sealing Kit (ATC13-1)

Common signs include oil spots on your garage floor or dark, greasy residue around the shaft output areas of the transfer case. You might also notice a burning oil smell if the fluid drips onto the exhaust system while driving.

This kit is designed specifically for the ATC13-1 transfer case, which is commonly found in modern BMW G-series vehicles, such as the 5 Series (G30), 7 Series (G11/G12), and X3 (G01). Always verify your transfer case type before purchasing.

Replacing transfer case seals requires precision and specialized tools to ensure they are seated perfectly. If not installed correctly, they will continue to leak. We recommend professional installation to avoid damaging the shafts or the housing.

If the seals were already brittle or worn, the fresh oil (which often has better detergent properties) can sometimes find its way past the old rubber more easily. It is best practice to inspect or replace seals when performing major drivetrain maintenance.

A small leak can lead to low oil levels, which causes friction and overheating. In the ATC13-1, this can result in premature wear of the internal clutches and gears, potentially leading to a total transfer case failure that is much more expensive than a seal kit.