ABS tone ring contacting sensor


Nov 6, 2017
Did front rotors on an '03 2wd Ranger today. First side I noticed a weird noise when spinning by hand and snugging spindle nut to seat the bearings.

Took it apart and found the tone ring had been contacting the sensor. Vehicle only has 89k so I'm wagering what I took OFF was OEM and I was installing O'Reilly rotors which I think are Raybestos.

Thus I'm inclined to blame aftermarket parts. It appeared to me the tone ring is just pressed on so I grabbed a metal oil filter cup wrench and threw it in the arbor press. I pressed the tone ring down a bit more....was afraid I went too far as it loaded up and popped but I'm not getting an ABS light so ignorance is bliss.

I'm not sure if it would have been detrimental to ignore the minor contact but I'm also not sure if the magnet can "see" the windows if it's in CONSTANT contact with the ring?

Either way it didn't give me warm fuzzies to know the cheese grater ring may have been self-clearancing the sensor

Note the pics are after just a few revolutions by hand. After many miles at highway speed I figure it would have either worked itself out or things could go very wrong
Aug 28, 2017
near Cincinnati, OH
Seems like it migtht've had the potential to heat up the sensor, making it brittle and prone to break. It wouldn't surprise me if it still worked to sense rotation since it has fairly wide slots between each tooth of the ring.
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