Differential is out...now what

[blkranger2]

I've been a long time reader here getting advice for fixing my truck,and its been great,especially the tech library.So here's a little background of my problem. I bought my 95 ford ranger 4x4 6 years ago,it runs like a top,its my daily driver,but it has always made a awful sounding grinding noise while it is in 4x4,I mean really loud to the point it gets annoying and you can hear it from the out side too.But the 4x4 has always worked good,never slipped and pulled me up some steep hills..Well today I pulled the front axles and the front differential.The u-joints was in good shape.Not froze up,and I was expecting to find a bad ring and pinion gear,but they was not wore at all.So I checked all the bearings on the inside and they was nice and smooth.I am confused.I was so sure it was in the differential.I know its not the hubs causeing the noise,as I replaced the auto hubs with manual hubs not to long ago...It must be in the transfer case.Any ideas on what this could be?

 

[1994_4x4]

It must be in the transfer case.

That's my guess. Can't see it being anything else. It'd also look into a manual t-case conversion while you're at this little adventure.