tranny noise

[Mirock]

Hi everyone just recently purchased a 95 GC L6 4x4 122k with automatic transmision .Yesterday i did noticed a strange sound like grinding not too loud ,at first i thought about the brakes but they checked out to be fine .Then i raised a jeep on 4 jack stands and put it in a gear the noise start coming from a tranny area ,weird thing is it goes away after O/D is turned off or lever isn't on a D position .Is my tranny on the way out or it could be some minor easy to fix thing, Thanx for any info in advance.

By the way the fluid and filter are brand new.

[Ron68]

Check the fluid and it's condition in the transfer case. Be careful removing and reinstalling the drain and fill plugs, as they can crack the bosses in the rear case half if too tight.

I had a noise like that in a NP242 tranfer case in an 87 Cherokee. At around 325000 miles the drive chain had stretched and was so loose it had worn a hole in the case and I lost all my fluid.

[Mirock]

i did check a transfer case fluid , it's nice lookin and full ,and acording to a previous owner TC was rebuild a year and a half ago ,so i'm thinking it' got to be something in a tranny .Late saturday i did made one more test ,rised a vehicle i put transfer case in neutral ( i think its supose to be completely disengage from the tranny then)i throw a tranny in a D position and while i was rewing up the noise start to ocure again and is going away when O/D bytton is pushed to disangage .My conclusions is that something is wrong with tranny ,but i have to find out what and how to fixed ,so i'm counting on any inputs from you guys.THanx