weird grinding noise from axle

[redrider]

I have an Auburn Pro differential, 4.10 gears, Moser 28 spline axle shafts and new inner and outer rear wheel bearings.

I recently developed a kind of binding grinding noise from the rear when making slow left or right turns going forward or in reverse.

My mechanic took of the rear cover and found all the moving parts rotating freely. He put in synthetic gear oil and said wait awhile to see of the noise goes away. Still grinding!?%&#@ Straight driving does not cause any noise.

Please tell me what it could be. I don't want to blow a rear end going 80 on the highway.

Thanks

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88 GT mass air conversion from 90lx, Cobra Intake(ported/polished lower),Edlebrock Heads(ported/polished),24# injectors 70 mm BBK TB, 73mm C&L, 347 SB, Wolverine custom cam, 150 shot Nitrous, BBK 1 3/4 long tubes, BBK off road H pipe, Dynomax cat back, alum driveshaft, Konis,Southside Bars w chromemoly torque boxes,AOD w lentech valve body, B&M MegaShifter, 4.10 with Auburn diff, SVO springs, subs, cross drilled rotors,MSD A6 w ign retard, black magic fan etc.