[camppain]

make sure for yuour lsd there is enough gear oil in there if not it could have a bad preload where you need to d*ck around with shims

this basically means that the ring and pinion gear arent making the correct contact to each other causing a humming.

i hope thats not it

as for the crunching when braking could mean your rear rotors need to be machined

i had that when i went in reverse and they where warped so i just machined am and sanded down the pads a lil. resolved the problem