After a few days of troubleshooting I finally figured out that my daily driver's ABS is kicking in consistently every time I slowly go through the 18-22 mph range (ie buzzing noises). And when coming to a stop (0-5 mph) the brake pedal shudders nearly every time. After pulling the ABS fuse, all the symptoms disappear. The cause....a cracked, left front reluctor/tone ring.

A new left front axle will run $130 + labor. A new reluctor ring is probably $30-$50. The labor on installing a new axle is probably less than replacing the tone ring. I'm not even sure if any shop would install just a new ring. Car is a 2002 with only 63K miles. Accelerating through 20 mph eliminates the pulses/buzzing. But if you hang around that speed while coasting (brakes not applied), you get seconds worth of buzzes and pops like a fog horn as the ABS hydraulics does its thing. Seems hard to fathom why that only occurs just from 18-22 mph. Why not 10-20 or 30-40? Something else I learned today. There's always been a pop/buzz whenever the car speeds up to 10-13 mph. I always assumed that was some "standard" function of the 1-2 shift. Now I find out it's a self-test feature of the ABS. The old Mopars were so much simpler....lol.

Can the crack in the ring be inexpensively repaired/metal filled? Or is a new axle the only logical repair? Apparently, it's fairly common for the front reluctor rings to rust, expand, and then crack. The other side will probably follow. I have to think the severe pot holes on I-95 this winter didn't help things any.

replace it. Even if the tone ring is slightly longer or shorter than it should be when you get done it will make the ABS performance worse. Tone rings usually not available separately for ABS.

Thanks goldduster318. Replacing it is probably the best course. If the CV/shaft assembly is prone to fail anyways any time in the next 6 years - 50,000 miles (115K miles total) - then replacing the part now or then is not all that much different.