So i replaced the transfer case switch, put it up on a lift today and it still acts like not enough vacum pressure, so Im poping out the vacuum actuaator under neath theb attery and I had 2wd selected when i shut the truck off, the Actuator is actually engaged when i took the battery box off i will post pics soon, but I am pretty sure and hoping that this is it, after all this work, $18 on the transfer case switch and i managed to find an actuator for $62.32, autozone for $49.99 not in stock...Update tonight!

 

Sorry, I was stuck on the prior posts on this thread. Blazin00LT was correct. I gave a link to AZ's actuator not the vacuum switch.

 

Well here are the pics of the actuator and pics after getting the battery box off, all put back together and works perfectly! and when i went to take it apart it exploded and was full of this liquid stuff as well not sure if it was suppose to be like that or not but it was collapsed and vehicle was in 2wd when i took it apart

 

Looks like it was full of auto trans fluid from the xfer case. I'd check the level or flush it out if it is due.