So I just replaced the rear wheel hubs on my daughter’s 2018 Subaru Crosstrek.  The dealer quoted her $800, and I told her I’d do it for free if she bought the parts (about $100 each).  Her boyfriend helped.

It took the 2 of us about 4 hours to do the job.  The concept is straightforward, but the old hubs were heavily rusted into the knuckles, and it took a lot of sledge hammering and chiseling to get them loose.  But we got it done.

Took it for a test drive, and immediately the traction control, hill hold, and ABS lights came on, and the steering got real stiff.  It felt like the power steering was out, but that didn’t make sense because we didn’t go anywhere near the front of the car.

Plugged in my scan tool and it said right rear wheel speed sensor was bad.  I unbolted it and pulled it out, and sure enough, it was broken off.  So I ordered a new one (about $40).  4 days later, it came and I installed it.

On the next test drive, all the lights went off, and it was good at first.  But then after half a block, the steering went stiff again and the warning lights came back on.  I pulled the sensor out and looked down the hole into the hub.

I found the problem: there is a thin little shield on the end of the axle that protects the sensor (see image).  We had bent that somehow so that it was cutting into the sensor on every revolution of the wheel.

So I took it all apart, bent the piece back into shape, and put it all back together (20 minutes to do the job this time - thanks antiseize!).  Prayed, and took it for a 3rd test drive... Success.

So: lesson learned.  The ABS parts are fragile.