I had a shop change out my posi unit in my 8 3/4 center section. they were quiet when i dropped them off, just didnt spin both tires, now they are loud. they roar so much you have to talk loud in the car to the other person so they hear you.
i pulled them back out and i am not sure what he did. I have only set up one set of gears and they were not noisy at all.

It is a 741 case 3.91 gears, I cant remember if i had him change the yoke or not but it seems a little loose, the yoke and pinion gear has some play in and out. I didnt think there should be any play there is that right?
I am rebuilding the clutch type posi unit to put back in it and want to fix the noise while i am at it. I have some gear grease ordered to check the pattern.
any ideas?