Is there any warning/noise/indication that a transfer case is on the verge of failing? I have a knocking noise everytime i start/stop, put into gear, make a 2/3 point turn, go over a bump etc. It sounds as if it's coming from underneath the driver seat. A mechainc told me it's the transfer case and it needs to be replaced. This is a 1900 fix. It's a 4wd 97 tahoe with 250K miles on it. So a transfer case problem would junk my car. Is this the noise such a problem would make? It seems to me it would have something to do with the suspension or drive shaft. Let me know. thanks.

 

It is possible that it's the transfer case. You could salvage one from a junkyard and do the swap yourself for a lot less money.