ATC700 Transfer Case

The newest edition to the transfer case line for the BMW X5 is the ATC700. Also used in the X6, this transfer case is not very different from its predecessor the ATC500.

They both have a transfer case actuator or shift motor and sprocket assemblies with frictions and steels. Much like the ATC-500 and the NV125 it replaced the chain has a tendency of stretching. Once stretched you will hear a popping noise coming from under the vehicle when you hit the gas.

At this point you want to replace the chain asap. If left unfixed the drive and driven sprockets can go bad increasing the cost of the repair significantly.