Transfer case problems 2005 4.4i auto

[colecruse]

Long time user of xoutpost but first post. I have 2005 x5 4.4i auto. My transmission feels like it is slipping in every gear except first. I have read many posts with similar problems. I'm thinking its the clutches in the transfer case. I have unplugged the actuator and it shifts fine. Plug it back in and it feels like its slipping. Does my x5 have clutches in transfer case or is it a chain? And if it has clutches can they be replaced? I have changed transfer case oil and front diff. Both looked and smelled burnt. TC was the worst. I put the correct oil in. What else could be the problem?