Raul Deu

Alright so when I start slowing down oamr it gets louder a bit when I brake. I start hearing a whirring/grinding noise almost like a train on tracks going by in the rear of my Na . It started after I had all my diff seals replaced, I checked the fluid level and the diff was over filled from what I can see so I let it drain to the proper level but it still makes the noise. Anyone have similar issues or know what’s going on and how to fix it? If not I’m sending it back to the shop that did my seals

(Clutch in has no effect on the noise so not transmission related as far as I can tell)