I think it may not be normal- I have an old diff sitting in a box and I just now turned the drive shafts and it makes a soft, gentle (no other way to put it) clicking sound which sounds normal to me. I don’t see why you can’t move the inner and outer parts of the sychromesh to new splines, but the main thing is to change the balls and springs. A decent manual gearbox shop should be able to do it as was done for me a few years ago.
Anonymous