195,000 mostly paved road miles, well maintained FJ 55. Transfer case has been getting more growly sounding. Mostly on level ground, not really on or off the gas pedal. How does a transfer case die? Grenades and locks up? Just gets so noisey that you gotta fix it? Hoping it doesn't eventually just blow up. I have searched this tropic a lot here lately, but not finding what I want. I have another trans and transfer from a good running '78 I parted out years ago. I don't recall it was noisey. So, if I keep running it as is what is the prognosis? Thanks in advance.