This is a new one to me so just throwing out a hail mary in hopes someone knows something. Search gave me nothing. I've got an 18LC with 103k. Took in to my local indy Toyota mechanic about 2 weeks ago for all the routine maintenance - flushes, belt, etc. Also replaced the rear brakes. Yesterday, I was getting the ABS dash light (and some others) off an on. Also, while braking, I was getting the ABS feel in the brakes at anything except the lightest braking. I noticed this morning that there was brake fluid on the garage floor and fluid splattered inside the wheel (rear driver's side). Took it into my guy - he said the 2 week old brake fluid was dirty and he feels strongly that the ABS module or wheel inside the rear axel must be cratering. He drained the fluid resealed it but the problems remains. He still thinks it's the ABS module/wheel inside the axel and suggests I take it to the dealer as they have the tool to get in there. I have good reason to trust the guy and he says he explored all the ways he could have caused an issue during the brake job. Anybody heard of this? Thank you!!
Brake fluid leak, ABS
- Thread starter GranolaJoe
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I’ll guess it’s something related to the brake job. Maybe a stripped out bleeder on the caliper? Where is it leaking? Maybe also a damaged ABS sensor? Maybe a bad flush job? There is no brake line or ABS inside the rear axle, so I don’t know what’s meant by that. Was the caliper replaced, or just the rotor and pads? It could be a defective caliper? Leaking brakes are extremely rare on a 200.
The only part within the axle that has anything to do with ABS is a “tone ring” that gives the ABS brain positional sensing of the wheel, so it knows when to do ABS things. This tone ring is merely a special wheel bearing side seal with magnetic stripes on it that pass by the relevant sensor. Yes those do go bad when the wheel bearings get really bad, but that’s usually closer to 150k if not 200+, and they don’t behave as yours does.. they just throw codes.
I have a decent understanding of these systems and can’t come up with a way that could cause a leak. Far, far more likely is the leak has something to do with the brake job, whether it was allowing a piston to push too far out, undue stress on a caliper line, bleed valve not closed enough or stripped, etc.
I have a decent understanding of these systems and can’t come up with a way that could cause a leak. Far, far more likely is the leak has something to do with the brake job, whether it was allowing a piston to push too far out, undue stress on a caliper line, bleed valve not closed enough or stripped, etc.
nwfl4runner
GOLD Star
Pull your abs sensor - I bet it’s covered in gunk - looks like wheel bearing - you sure it’s brake fluid?
Sorry, but i don’t think this has anything to do with the ABS pump. Is it brake fluid that is leaking all over the place, or differential fluid? They are very different from each other. Color, viscosity, smell…
Is the brake fluid level dropping? It’s not possible to loose brake fluid without the level dropping on the reservoir on the master cylinder.
Is the brake fluid level dropping? It’s not possible to loose brake fluid without the level dropping on the reservoir on the master cylinder.
Yeah, diff fluid making it out there pretty much has to be a bad wheel bearing. It's black from being mixed with brake dust. Though it's worth checking your diff fluid too.
Odd that it would happen just after a brake job..
I wonder.. Do you tow a bunch? Own the vehicle from new? These bearings dying isn't unheard of but I'd consider yours a somewhat early failure.
If you're curious what is involved:
(It's a big job)
Rear axle bearing change
Back again with something I hope will help some people eventually. I'll try not to make this too wordy, but there is a little background. I spent months tracking down a driveline noise and with the help of some board members and especially @CharlieS narrowed it down to a passenger side rear...
forum.ih8mud.com
- Thread starter
- #9
Bloc, thanks. No, don't tow much at all. Bought it at 60k. The recent brake job and the ABS braking issue (with dash lights) had me confused for sure. Haven't experienced that before with a bad bearing in other vehicles.
Are you sure it's not a leaky brake caliper and just looks darker because of the dirt? If the pistons were pushed back into the caliper carelessly the rubber boot could easily tear and end up leaking fluid out. I've personally seen these boots crumble on an '08. Granted I'm not quite sure why that would throw an ABS light, unless the fluid got low enough that there's air in the master cylinder, but it seems much more likely than a wheel bearing/seal failure just given how closely this seems to have happened to the brake job.
Too bad, the caliper is a cheap and easy fix :-(
A broken piston boot does not create a leak, at least not so quick. It takes a LOT of driving for the dirt to get to the piston seal and damage it. Even then the leak is not as massive as this one.
I have to say, if it’s differential oil I’m no longer confident about your mechanic. It’s really mechanics 101 to know the difference between fluids and if he inspected it and called it dirty brake fluid I’m not sure I’d trust him any more.
@laserturbo91 did brakes in the parking lot just before LCDC last year and when pushing one of the pistons back in the boot tore, and within a few minutes fluid was dribbling out. I've never tried to rebuild a caliper so maybe there are multiple seals and the outer boot was already hist last line of defense, but there was no fluid visible until that happened so in his case 100% when the boot tore the fluid started leaking. The leak wasn't massive but he didn't reassemble and try to apply the brakes either... I imagine the pressure would shoot fluid out rather quickly.
Doesn't sound like the OP is low on brake fluid though so this may not be the cause, just visually from the mess it's where I would've expected the issue.
- Thread starter
- #17
Update....I get to spring for a new wheel bearing assembly and will probably replace the (brand new) brakes on that side since they been oil saturated for days. I am still a bit stumped why/how the bearings failed at 100k. I don't tow or carry extra weight. Unlucky I guess.