Front differential

It is normal, the wheels and an actuator engage it.

So what could my problem be with my transfer case? I got the truck with a transfer case that was locking up. So the "dealer" put another one and it stopped locking up but instead slowly rolls while in park and whines and slips on take off almost through first gear and then its fine. After a few months it burned out leaving me stranded out in the middle of no where. I got a rebuilt one from a place called transfer case express. I put it in and after the first day it started whining too but very faint. I have another rebuilt tcase waiting to go in but I need to find out whats going wrong before I mess this one up too.

Slight whining in a tcase is pretty normal. Have you scanned for codes as well? Has the truck ever been hit? Something may be out of line causing it to burn up also it may be an internal problem with tcase. It really has to be physically looked at. Also see pictures for any of these causes especially last one when putting in a used tcase rebuilt should have this done already.

Its been 2 transfer cases now. One used that burned up completely and now a refurbished one thats starting to sound like the old one.

The was never in any reported accidents and I can see any frame damage.I scanned it today at a friends place and it had 0 codes. The whining is accompanied by slipping as well.

Did you read all the pics I sent in last reply? I'd be yours has to deal with the very last pic dealing with pump that is why it burned up. If this t case was built by a rebuilder and not out of a junk car take it back they should have a warranty on it and will fix the problem.

Yes they sent me another one. Im hoping that when I put it in its not gonna do the same.I dont wanna ruin this one as well. So im taking my time to see if anyone knows what could be causing it.

Usually the transfer case does not slip, are you sure you don't have a transmission problem?