When braking (not always) under 40mph I hear a light humming from the wheels which gradually gets louder (like a droning noise)to the point that the right a pillar seems to sound to be shaking or humming along with the wheels (which I know are suppose to be loud to begin with.

I dont know if this might help to diagnose but one time at a parking lot I was going down one level on those turns (left to be exact) and it felt so smooth and then the ride roughed up again going straight.

Any help would be great thanks

 

looks like your rotors are worned. either that or you''re going to hear a metal to metal grinding sound. pads gone.

I don't know what else it could be. maybe you're rubbing on something...

 

what he said or your felling high pitched vibration from your trans.. highly unlikely though