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.