I replaced the rotors and bearings a couple of weeks ago in my 2000 Explorer 2wd. It seams as though I did not install the races with the bearings in the new hubs. Do the hubs come with races or should they have been pressed into the hub? Ithought I just needed to install bearings when I originally did the work. I thought the humming noise was coming from my tires, but I had them replaced and the humming noise is still present. Any guidance would be much appreciated. This forum is a great tool!