The transfer case shifter on my truck makes a kind of random rattling clacking noise at freeway speeds 45mph and up. Doesn't seem to matter whether there is a load or not, will even do it if I knock the trans into neutral and coast. Has done it on and off for the last 10k miles. Changed fluid, looked brand new with no metal. You can move the stick around and it still does it which is opposite of what I've read in different posts. Shifts into all positions fine. Transmission was just rebuilt along with the drive shafts. No change. Replaced T-case seals while it was out during trans rebuild and shafts rotated smooth with no play. Just got back from a 1200 mile trip and it was kinda annoying. Just hate to tear into the t-case if it's just a shifter thing. Any Ideas??? Thanks!!!