Clunking/grinding noise in rear differential

[garym]

I just did a transmission/clutch change in a 01 Z06. I dropped the exhaust, rear suspension and torque tube/trans/diff. I separated trans/diff/torque tube into 3 separate pieces and then reassembled with new trans. Put new clutch in, put torque tube assembly back in, put rear suspension back in, and exhaust back on. I now have a clunking/grinding/rubbing noise whan making slow turns and a little vibration at about 30-50 when cruising. When I punch it or take corners hard, seems like there is no noise. Rechecked half-shafts to make sure they were fully inserted. I know the lim-slip diffs are a little temperamental, but I put the new Amsoil 75W110 in with a bottle of friction modifier. Didn't think the jump from 90-110 would be a big deal. Could the thicker oil be causing the diff clutches to have problems? Any other ideas??

[Pbalias]

i had a similar problem once on mine...turns out I damaged the input shaft bearing while mating the torque tube to the motor.