In this video I go over a lot of common problems seen on the BMW transfer case. Most of the time you will not get any fault codes when you have an issue with your BMW transfer case. The most common symptom feels like a misfire or chatter while driving or cornering. You may have some fault codes and a 4x4 ABS warning.
FC 5F3A Transfer case malfunction
FC 5463 VTG Transfer case mechanism faulty
FC 539E Transfer Case Malfunction
FC 54C6 Transfer Case Fluid Replacement.
For the fluid service internal, BMW in there infinite wisdom decided that you, as an owner, would only know when the fluid was need to be replaced by setting a fault code that would have to be read out of the vehicle using a scanner. By the time you see this code it may already be too late to save the transfer case. But before considering replacement of a very expensive transfer case there are some steps you can to help save your transfer case or transfer box. Change the fluid in the transfer case.

FLUID TRANSFER PUMP (NOT SOLD ON AMAZON)
https://www.finditparts.com/products/...

CHAPTERS
00:00 TRANSFER CASE SYMPTOMS
01:43 TRANSFER CASE OIL CHANGE INTERVAL? FC 54C6
02:21 TRANSFER CASE DIAGNOSIS
03:30 CONFIRMED ISSUE! NOW WHAT!?
04:05 OIL TRANSFER PUMP YOU NEED THIS TOOL
05:19 FLUID CHANGE PROCEDURE VIDEO
07:05 HOW THE TRANSFER PUMP WORKS
09:00 BMW HAS A SERVICE BULLETIN ON THIS ISSUE DRIVE 120 MILES AFTER FLUID CHANGE