SOUNDS LIKE POSSIBLE BAD WHEEL BEARING, THE ONLY WAY TO KNOW IF IT IS DIFF OR BEARING IS TO ROAD TEST AND DIAGNOSE, I USE A CHASSIS EAR WHEN SYMPTOMS ARE NOT OBVIOUS, BUT I CAN DETERMINE FOR SURE WHICH IS DEFECTIVE. HOPE THIS INFO WAS HELPFUL, FEEL FREE TO CONTACT ME IF YOU WOULD LIKE TO HAVE YOUR VEHICLE DIAGNOSED.
SINCERELY, RYAN MODE MODE AUTOMOTIVE 858-361-4645 MODEAUTOREPAIR.COM
I have the same problem as yours - grinding, vibration ( as if you are doing an engine break when you slow down). replaced mine thru dealership and paid just the labor and parts included as warranty even if I had 65000 miles already.
if you jack each front tire off ground .[ can be done 1 at a time ] grab top and bottom of the tire with your hands not sides of tires . see if you can move the tire at all for example pushing in on top of tire while pulling outward on bottom of tire and visa versa. the tire should not move at all if it does its definitely a bad wheel bearing. if it doesn't move at all it could still be the wheel bearing or the differential may need to be re shimmed. you will need expert diag. but if either tire has moves top to bottom then its that wheel bearing and the diff. is most likely fine. I say most likely because it could all be it very slim have problems with both. hope this helped