noahjk123

I’ve finally solved my ABS problem!
This is going to be a long and somewhat detailed writeup on what my symptoms were, my diagnosis, what the actual problem was, and how I fixed it. I’ll highlight the main points so you can skim through if you wish. DISCLAIMER: I’m not a mechanic. I’m an engineering student who loves his GS300 but doesn’t have bottomless pockets, so I often take the DIY route on “simpler” jobs.
Symptoms: ABS was engaging at low speeds when approaching a stop. There were no lights on the dash like VSC off or ABS. The ABS buzzes when coming to a stop and the anti-lock braking activates, inching the car forward a couple inches. It’s not exactly a safety issue but it becomes seriously annoying after a while.
It began happening only when I was doing a hard turn (like when pulling into a parking spot), but then it eventually got to the point where it happened at every stop. Very big PITA and very frustrating. Whenever there were passengers in the car I’d get questions like “what's that buzzing noise?” or “why does it do that when you stop?” So I began the long process of diagnosing the issue.
Diagnosis: I put an ABS code scanner on the car with no apparent codes. I brought the car to Lexus of Northborough, MA, where they told me there was a disruption in the ABS circuit on several wheels. Before you comment, just know that I tried all the simple fixes (Cleaned ABS sensors, replaced the ABS sensors). Nothing. Problem still persisted. I did some research on the forums where I found it could be an ABS tone ring problem. Hint Hint, it was. So I took a look at my ABS tone rings when I removed the sensors. They looked a bit worn, but not rusted or cracked like some people on the forums suggested. I tested that this was the problem by sanding down the ABS sensor mating surface so that it got a better signal from the tone ring. It worked but only temporarily (a few months, then back to ABS problems). But I knew I was getting close.
Problem: RUST!!! If you live in New England, or anywhere where rust is common and you’re having the same symptoms as me, I’d say this is your issue. It wasn’t the ABS tone ring that was rusted, but actually the inside of the knuckle where the tone ring spins and ABS sensors read, causing excessive wear on the tone ring, and therefore a disruption of signal in the ABS system.

Rust buildup inside the knuckle. This causes the dust shield around the axle to warp and it crimps around the ABS tone ring. This is what's causing the wear on the tone ring

Here you’ll see the buildup of rust that actually caused the ABS sensor to wear over time
Solution: For me, I needed to replace ALL of the wheel bearings, and ABS rings. This means for the rear you have to replace the axle (you can find the ring online for the rear but your axle might be already on its way out if your car is over 20 years old like mine.) The fronts were done because my wheel bearings were just bad and starting getting loud. It made the problem better, but then it came back after a few months again. It was only when I changed the rear wheel bearings and ABS components that the problem fully went away.
DIY fix: If you want to change the front, I could tell you how to do it, but 1A auto has a perfect tutorial on youtube. Use it. Here’s the link:

You Tube

For the rear wheel bearings and axle, there wasn’t as much info. So I had to watch bits and pieces of videos from other cars to figure out what to do. I also got the factory service/repair manual. I would HIGHLY recommend getting this. It gives very detailed diagrams that you can use for disassembly and finding part numbers. It's also good for finding torque specs for reassembly.
FYI, you’ll need a good amount of tools, including a hydraulic press. Lucily, I’m able to use the garage of someone close to me, and they’re stacked with tools.
Steps:

• Remove wheel, brake caliper, brake rotor, and parking brakes
  
• Disconnect:
  • upper control arm nut
    
  • Lower control arm bolt/nut (make sure to mark alignment specs)
    
  • Toe arm nut
    
  • Other lower control arm bolt/nut (Not sure of the name, trailing arm maybe?)
    
  • ABS sensor
    
  • Parking brake cable
    
  • Cotter pin and axle nut
    

Now, you can remove the knuckle from the car, where you’ll begin to disassemble it. There’s a few nuts to disconnect from the dust shield. Next, with the dust shield loose, you want to figure out a good way to press out the hub from the knuckle. This can be quite tricky because there's going to be a great deal of force applied. You want to avoid bending the dust shield, because it will make your parking brakes not fit correctly. I ended up using a socket to press out the hub.

Here's my sketchy setup for pressing out the hub. It didn't even end up working because the hub and bearing were so seized. I ended up whacking it with a sledgehammer which worked.

The hub was rusted in so bad that I actually bent the crowbars...
I resorted to moving this setup to the ground and whacking it with a 20lb hammer. Just two hits and it worked!!! Next you have to take out the snap ring and the bearing, which is much easier to set up without the dust shield in the way. Also, remove the small metal dust shield on the inside of the knuckle with a picking tool and some strong pliers.
Now, with a bearing-less knuckle, you gotta do some DEEP cleaning.
Using some sort of handheld grinder, remove the bubbled rust on the inside of the knuckle. This is what was causing the issue, so you’ll need to grind it down so the inside is perfectly round/ shiny. Using a wire-wheel brush, I cleaned up the inside, making sure not to remove more metal than necessary (you still want to have a proper fit when you're done).
Once this is done, I suggest painting the outside of the knuckle to slow the spreading of rust into where the wheel bearing sits and where the axle goes through. I also painted my dust shield even though it's starting to rot away. I would've bought new ones, but they’re over $350 from Toyota!!! Ridiculous!!!!

At this point, with the paint drying, you can also remove the axle from the differential. You’ll need a 10mm hex bit socket and probably a large breaker bar. You’ll also have to secure the other side so the diff isn't just spinning. Then just knock the axle off the diff with a chisel and hammer and it should come off (mine did even with a bunch of rust). Now you can put the other axle on. I suggest buying some new axle bolts from Lexus/Toyota. There’s six bolts per axle, and two metal gasket plates. I reused these gasket plates and just cleaned them up with a wire brush. Make sure to suspend the axle from either the UCA or the coil springs, so the axle isn’t damaged from hanging. I also surrounded the outer end of the axle with cardboard so it doesn't bump into other suspension parts and damage the tone ring.
After the knuckle is painted, give the inside another cleaning with a wire wheel tool to clean up rust and any overspray. Make sure you clean the surface that the ABS sensor bolts up to, so there's a bare, rust-free, and flat surface to seat. Also make sure you clean the inside of the hole that the sensor goes into. Clean the inside with some brakleen, and you should be good to start reassembling in reverse order.
Pressing the new bearing and hub is much easier with a clean surface and some wheel bearing grease. Also make sure the knuckle is PERFECTLY perpendicular to the knuckle so it goes in perfectly. If you do it right, it shouldn’t take a whole lot of force with the press.
Before you put in the hub, make sure you put on the brake dust shield. Now, with the hub, brake dust shield and wheel bearing inserted, you can put in the ABS dust cover on the inside of the hub.
Now you can put it all back on the car!
Here’s the parts I got, and where I got them from. I don’t have the part numbers so sorry about that! Just call your local Lexus/Toyota dealership parts department and they’ll help you out with that
For each side of the rear:

• Wheel bearing (I got Timken bearings off Rockauto)
  
• Axle (Rockauto)
  
• Hub (Rockauto)
  
• ABS dust shield (Lexus)
  
• Wheel bearing snap ring (Lexus)
  
• 6 x Hex bolts for axle (Lexus)
  
• Axle nut (Lexus)
  
• Locking nut for Upper Control Arm - I stripped mine (Lexus)
  
• Axle nut crown (Lexus)
  
• Cotter pins (hardware store)
  
• Paint/primer combo (hardware store)
  

I tried to be as detailed as possible without being excessive. I made this writeup so I can help anyone suffering from this, as I spent many hours researching this, and even more trying to solve it!
Anyways, here's my GS.





EDIT/UPDATE: Do yourself a favor and replace both of the lower carrier bushings on the knuckle!!!!! Don't be an idiot like me and wait until they start making noise to remove the knuckle all over again...

kajencik

This is very cool, my GS430 currently has bad right front ABS sensor, so no ABS at all, but I understand before that went wrong, it was doing exactly the same thing. And we do get rust so this is likely the issue. Looks like hell of a job, but in the long term very worth it... Could you estimate how long it took? I'm thinking how much should a shop charge for this.

Did you also need to replace all the ABS sensors or only the rings? I notice in your write up you maybe replaced them before doing this... Did you go with OEM one or aftermarket? I found the OEM ones only for more than $300 a piece but I also read somewhere the aftermarket ones don't really work.

noahjk123

I did end up trying new (aftermarket) ABS sensors in the front. It made a small difference but didn’t solve the issue. I’d check the sensors first. They’re usually covered with metal shavings. There’s a possibility you’ll have to change the sensors in addition to the bearings. You’ll have to play it by ear.

Also, the front bearing job is slightly different but pretty similar concept. The 1A Auto tutorial is given in my post. All together for the fronts I’d say ~12-18 hours of labor if it’s your first time doing this and nothing goes terribly wrong. About 2 days of the car out of commission if you’re committed to doing it.

I asked a shop what they would charge before I did this job and they said $1000 just for one side on the front! To be fair, I didn’t shop around too much for different mechanics to give me a quote, so not sure how outrageous that is. For me, it was 100% NOT an option so I had to bang it out myself. Hope that helps!

kajencik

I will probably not do this myself, but I can see how one corner could take a whole day. Fortunately the labor is a bit cheaper where I am, so I'm probably looking at around $800 for 4 full days of work. I also want to fix/upgrade the bushing and other tired suspension components in the process, so it helps to include this estimation in the overall bill. Maybe on the expensive side, but I just love the car and plan to run it for at least 10 more years if possible.

tinman

Thanks for posting this, I've been down the ABS diagnosis road too and I couldn't figure it out. Thank you for this write up, I'll check if this is my problem.