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?

If you lift the rear wheels and just rotate by hand, you could probably narrow down where it's coming from. I have seen a broken ABS ring and a bent sensor at a rallycross, it made some awful clunking noises even at very slow speeds.

sloppy drive shaft or carrier bearing (center support)? my first guess, but maybe not the most likely.

grab it, pull, push, wiggle it and see .

 

bad rear axle? easy to see, just wiggle it.

 

bad rear bearing? this might be more likely, (cyclic thumping or humming, maybe more when turning at speed.)

have someone ride in the back seat and listen on each side to see which is louder.

jack up the wheel, rotate it by hand, listen and feel the spring for noise or vibration.

do the other side.

Edited September 28, 201411 yr by johnceggleston

all the tires the same brand/model/size and close to the same wear?

Check lug nuts.

Seperated belts in the tire?

Thanks everyone! Waiting for the friends with a garage to get home and dig back into it, will look at all the great suggestions and see what comes of it!

@Lucky, yes, all of the tires match and wear is pretty close to the same though they could probably have used one more rotation than they have

@Lucky, yes, all of the tires match and wear is pretty close to the same though they could probably have used one more rotation than they have

 

good - we have to ask a lot of basic questions when new folks sign-up.

Was the ABS sensor that had managed to mangle the whole drum. We are thinking we didn't catch it yesterday because it just a small piece of the sensor that was broken so not very noticeable. The drum was so mangled and jammed up inside that nothing moved right until pulling it apart at which time the entire assembly tumbled into the floor. Fun times!