I started feeling/hearing a bit of a grind from the back of the car a few days and knowing that we were about due for brake work he checked those and saw that one of the rotors definitely needed replaced. Just replaced rotors and pads on the back tonight and when changing them also found that the left rear ABS sensor had broken so removed the remaining piece until we can get it to the shop during the week. When I started to drive home, everything was good for about 5 miles (on the highway, about 55-60mph) and then all of a sudden another huge clunk and lurch feeling accompanied by a consistent intermittent 'thump thump' and light grinding. Seems like it's coming from the back in general but if I had to narrow it I'd guess more on the right side. Any thoughts?! Everything visually appears fine with the new pads/rotors but it's too late to pull apart again tonight. Could it be caused by the right ABS sensor also being broken and we just didn't see it earlier?