ABS problem with new bearings

Hi all,

I just installed Bilstein 5100s all around and new LCAs due to seized bushings, but when I went to get an alignment I was told it was not possible because I had bad wheel bearings. Which I knew, I just didn't plan on replacing until later this year. However, being in a time crunch, we decided against buying the bearing kits from one of the members on TW, and went ahead and bought 2 wheel bearing and hub kits from RockAuto, they are DuraInternational brand. Was a little unsure of the quality, but went ahead anyways because I could get fast shipping so that I could have the project done before my final college semester started and they were pretty cheap (should've been a red flag). Now that I think back I should have bought the pre-assembled units from one of the members here it would have saved tons of time and money.

So, I had the units pressed and installed them with my father, but now my ABS light is on. We took the sensors out, cleaned and replaced, then ran an OBD scan to determine which was the problem. Turns out both are malfunctioning so we came to the conclusion that the bearings had damaged tone rings from installation, backwards tone rings from the manufacturer OR none at all, if that is possible. I went ahead and contacted DuraInternational about it and am waiting for a response. Do you all think we should replace the bearings again? Is it possible to successfully replace the tone rings themselves? If they can even be purchased...

I'm still confused as to where the tone ring is located on the bearings and how it even works, can anyone explain that? Also, could it be because we did not measure the distance of the sensor and the ring on the stock bearings and installed the new ones wrong? Or is it possible if a magnet got close to the bearings and threw off the tone ring? or does the Tacoma tone rings have notches rather than magnetic?

Sorry for all the questions. I searched a ton but couldn't find enough info to answer all my questions. Any help or advice is welcome!

 

@BamaToy1997

He probably knows.

 

I just did my front wheel bearings, so this is fresh in my mind. The back of the wheel bearing "module" has the magnetic tone wheel attached - or should. It looks like a seal, but in fact is not a seal, but a series of small magnets within the ring. It does not use the traditional style of notched steel tone ring. Throw some iron filings on your old one if you still have it, you'll see what I mean.

I'm suspecting your bearings might have been cheap for a reason - but to confirm, you can pull the front ABS sensors, and insert a very small screwdriver to see if the ring on the back of the bearing is magnetized. If it is not at all (it is a mild magnet), then you need to remove those bearings.

 

I will have to do the screwdriver test... Do you think it is possible for a strong magnet in close range to damage the tone ring? I thought I read that somewhere but was not sure if it applied to the type the Tacoma has.

 

The Toyota ABS systems on the trucks are pretty interesting, to say the least. There is a small magnetic plate that is part of the inner seal lip on the back of the bearing. Some cheaper units are built without these, and are NOT compatible with ABS systems. Since I wanted to keep things simplified, I build every one of my units as ABS compatible, so that I don't have to worry about it.
Below is a picture that shows the magnet. It is the brown ring on the outside area.


If you do not have this ring, then your wheel bearing is NOT compatible with the ABS system and will need to be replaced.

The way the system works is thus:

The magnet is polarized where the side facing in is southern poled, and the side facing out is northern poled. The rollers inside the bearing are made of steel, and the roller cage is made of teflon. (non-metalic so it does not affect the magnet) As the rollers move underneath the magnetic plate they alter the magnetic field around the magnet. The ABS sensor reads this fluctuation and the ABS computer is programmed with the number of rollers on that side of the wheel bearing. This way the computer knows how many pulses it should see in a wheel rotation. The faster the pulses come, then the faster the wheel is turning.