Oil in ABS cavity - Is a little expected?

[Kanoe]

Hello all.

While servicing bell cranks today I decided to be proactive and have a look inside the ABS sensor cavity. Cr*p. Not dry as I had hoped.

175,000 Km, axles have never been touched. I found both sides to be similar. There is some gear oil in there. There is NO leak into the brake drum, no outward signs of anything leaking. There is enough gear oil that it is present in some teeth of the ABS gear, but there is not enough there to completely bathe the gear. Only 25-50% of teeth had oil present, and it certainly wasn't running down the gear as I turned the axle.

Has anyone seen this? Has anyone ever checked this cavity before the outward signs of a leak have shown up? I wonder if it is possible that it is OK for a little gear oil to be in there (hoping)?

Really hoping it is not axle seal time for me but at least my brakes are not damaged. Oh, diff vent extension has been done for some time so that should not be an issue here.

Thanks for any opinions.

 

[LittleCaesar]

Don’t sweat it. As long as you aren’t throwing a code....

 

[Kanoe]

Don’t sweat it. As long as you aren’t throwing a code....

Thanks.

I'm not worried about the ABS system. I am worried about leaking axle seals. Just wondering if this is commonplace or if I should be getting a jump on axle seals and bearings. I really don't want to poke that dog if I don't have to...

 

[I_bRAD]

Hello all.

While servicing bell cranks today I decided to be proactive and have a look inside the ABS sensor cavity. Cr*p. Not dry as I had hoped.

175,000 Km, axles have never been touched. I found both sides to be similar. There is some gear oil in there. There is NO leak into the brake drum, no outward signs of anything leaking. There is enough gear oil that it is present in some teeth of the ABS gear, but there is not enough there to completely bathe the gear. Only 25-50% of teeth had oil present, and it certainly wasn't running down the gear as I turned the axle.

Has anyone seen this? Has anyone ever checked this cavity before the outward signs of a leak have shown up? I wonder if it is possible that it is OK for a little gear oil to be in there (hoping)?

Really hoping it is not axle seal time for me but at least my brakes are not damaged. Oh, diff vent extension has been done for some time so that should not be an issue here.

Thanks for any opinions.

Unfortunately, if the seals aren't leaking, then where did the oil come from? Count your blessings that you found it early and don't have to redo the brakes too!

 

[LittleCaesar]

I would then just buy a new breather and not sweat it. Let the dogs keep sleeping.

 

[nevada]

Hello all.

While servicing bell cranks today I decided to be proactive and have a look inside the ABS sensor cavity. Cr*p. Not dry as I had hoped.

175,000 Km, axles have never been touched. I found both sides to be similar. There is some gear oil in there. There is NO leak into the brake drum, no outward signs of anything leaking. There is enough gear oil that it is present in some teeth of the ABS gear, but there is not enough there to completely bathe the gear. Only 25-50% of teeth had oil present, and it certainly wasn't running down the gear as I turned the axle.

Has anyone seen this? Has anyone ever checked this cavity before the outward signs of a leak have shown up? I wonder if it is possible that it is OK for a little gear oil to be in there (hoping)?

Really hoping it is not axle seal time for me but at least my brakes are not damaged. Oh, diff vent extension has been done for some time so that should not be an issue here.

Thanks for any opinions.

oil is getting past the seal. if its not getting into the bearing yet, just changing the seal is easy. get it done now before it causes a bigger problem.

 

[Wedgy]

You could just vacuum the oil out and see if it comes back, if it does then change the seals they're ~ 20 years old and do go bad. Keep an eye on it because if they leak they will destroy the bearings which is a much bigger and more expensive job, as well as having to do the brakes.
Doing just the seals is cheap and not a very big job and is a good way to save yourself a lot of trouble.

https://www.youtube.com/watch?v=AVhSDnw2ugo

 

[thegipper]

When I checked mine last year, I had the same thing going on. Some oil but not much, just enough to pool up between a couple teeth.

I check it every once in a while and never find any more/less oil. It may have been due to a clogged breather (which mine most definitely was) which has since been replaced. I checked both wheels for play and both have a tiny bit of movement which is nothing to worry about.

Just keep an eye on it and make sure it doesn't get worse. Or if you want to be proactive, at least replace the seals at this point.

 

[Kanoe]

Thanks all. Appreciate the advice.

Changing the seals sounds like the best option but I wonder if that will lead to more leaking? See Dr Coffee thread. I suppose flipping the retainer and changing the seal would be the best bet.

Has anyone been able to pull and flip the inner retainer without messing with the ABS ring? Looks like they are sitting right next to each other and may need to come off as a couple. The ABS ring is a bit on the expensive side.

 

[Wedgy]

The ABS ring is what the puller grips and I can easily see it bending as it's hollow and takes a huge amount of force, the guys at NAPA say they usually need replacing after being pulled. When I did mine I notched the retainer with a grinder to "relieve"(I made a couple cuts about 3/4 the way thru it but didn't cut deep enough to touch the axle) it and they came off pretty easy. I would much rather replace the retainer than the ABS gear.

 

[nevada]

Thanks all. Appreciate the advice.

Changing the seals sounds like the best option but I wonder if that will lead to more leaking? See Dr Coffee thread. I suppose flipping the retainer and changing the seal would be the best bet.

Has anyone been able to pull and flip the inner retainer without messing with the ABS ring? Looks like they are sitting right next to each other and may need to come off as a couple. The ABS ring is a bit on the expensive side.

no, just change the seal. you don't have to touch anything else.

 

[I_bRAD]

The ABS ring is what the puller grips and I can easily see it bending as it's hollow and takes a huge amount of force, the guys at NAPA say they usually need replacing after being pulled. When I did mine I notched the retainer with a grinder to "relieve"(I made a couple cuts about 3/4 the way thru it but didn't cut deep enough to touch the axle) it and they came off pretty easy. I would much rather replace the retainer than the ABS gear.

I pulled my abs ring off and reused it, no trouble. I actually pulled one side off twice because I pushed it on too far the first time around.

 

[Mchaz]

How are your wheel bearings? Any play or grinding?

If the bearings are okay, I'd be tempted to try just a seal replacement. It's really not a bad DIY project. You could try installing new OEM seals, and performing a grease test to see where on the retainer ring your seals are riding. If the seals are riding too close to the edge of the retainer you could try a different brand (aftermarket) seal to try to manipulate the seal position slightly. Dr. Coffee's thread on the subject points out that Toyota changed the seal design at some point, which can cause issues with the retainer ring position. His thread is definitely worth a read.

Changing the wheel bearings is a big job, and if they haven't been contaminated yet I'd definitely try to keep the diff oil out of them. Doing the job after everything is soaked in diff oil and road grime is nasty hard work that I wouldn't wish on anyone after having done it myself. Mine had been leaking into the drums for an unknown amount of time, and there was an incredible amount of crud stuck to every surface.

Sent from my RS988 using Tapatalk

 

[4Runner4Leon]

I agree with others that the seal has failed. Seals don't leak gradually over 20 years. It sealed perfectly for X number of years, and then started leaking. Once it starts leaking, it, well, leaks. It's just a matter of time before enough diff oil gets past the seal to get onto the brakes, into bearings etc. May be a week, a month, a year, I dunno. What I do know is that once it gets out, it'll make a big mess.

Now you need to be very careful with the idea of "just replace the seal". That's the whole point of the Dr Coffee thread and the retainer flip. The reason for this is that a new Toyota seal is different design/geometry from the original seal, placing the sealing lip into a questionable location, so close to the bevel that it may not seal correctly (or it may, it's on a hairy edge).

So you have two options:

1) Get a new Toyota seal, with the improved design which makes the seal more compliant. If you do that, I would suggest flipping the retainer, which does involve pulling the retainer and the ABS ring off. If you want to try to avoid that, you can just put in the new seal and do the grease test, and hope that the lip ends up away from the bevel.

2) Get an aftermarket seal. Those have the same (bad) design/geometry as the original Toyota seal, but if you got 20 years out of the original seal, you may get some good life out of the replacement seal. And because the geometry is the same as the original, the sealing lip will end up in the original spot and you shouldn't have to flip the retainer. One word of warning on this - I did that at first (got a National seal), and it leaked right away. OTOH, I believe that others have been able to get by by just replacing the seal. Worth a shot, I guess.

 

[mtbtim]

All the issues with just replacing the seals has been covered by others so no need for me to repeat. If you want to pull the axles only once and be done with it for a long while, replacing the bearings is in order. I'm in a shitty internet location in Yellowstone so I can't link you the video @infamosRNR and I made. If you look up "Timmy the Toolman", you'll find our channel and the video we did for this job using the Dr Coffee method. If you just replace the seals, don't be surprised to find a splay of gear oil on the inside of one of your rear wheels way sooner than you would have hoped for.

 

[Kanoe]

Thanks again for taking the time to chime in.

I have read the Dr Coffee thread and watched Tims videos. Thanks guys.

I believe bearings are OK. I'm going to have another look today. Runners only got 175,000km or about 110,000 miles. The oil has not left the ABS cavity yet, at least not enough to see in the brake drum internals. There is not enough in the ABS cavity to soak the ABS ring, just some of the teeth have some gear oil on them.

I agree with Tim, I am a once and done kind of guy. However, parts are very much more expensive here in Canada than in the US. I would like to get by on just seals or seals and retainers if possible, and I would like to do as much of the work as I can myself. I am not set up for doing the whole axle R&R as Tim does.

Biggest stumbling block I see is getting the old retainer off and pressing the new one on if I do the Dr Coffee flip. Leaning this way.

 

[gamefreakgc]

Thanks again for taking the time to chime in.

I have read the Dr Coffee thread and watched Tims videos. Thanks guys.

I believe bearings are OK. I'm going to have another look today. Runners only got 175,000km or about 110,000 miles. The oil has not left the ABS cavity yet, at least not enough to see in the brake drum internals. There is not enough in the ABS cavity to soak the ABS ring, just some of the teeth have some gear oil on them.

I agree with Tim, I am a once and done kind of guy. However, parts are very much more expensive here in Canada than in the US. I would like to get by on just seals or seals and retainers if possible, and I would like to do as much of the work as I can myself. I am not set up for doing the whole axle R&R as Tim does.

Biggest stumbling block I see is getting the old retainer off and pressing the new one on if I do the Dr Coffee flip. Leaning this way.

Do you have your own press? If not, then the average machine shop will not be able to just press off the retainer and then back on. I just went through this fiasco myself since I do not own or have space to store a press. Had to find a compromise with the shop.

If you leave as-is, it will wash out the bearings like others said and accelerate their wear. It's not an overnight thing but just know you'll have to replace not just the seal but everything else. If you DIY it it's roughly $250 per side if you include new rear drum shoes and springs. If you have a shop do it, it's about $600-$800 per side depending on labor rates.

Putting in just a new seal might fix it for only $10 bucks though. They are a little tricky to get to seat correctly though.

 

[Kanoe]

Had a talk with the dealership about this. Independents seem to refer this job to the dealer rather than tackle it.

Service manager said given how it's just in the ABS cavity (and not much) and no apparent leak through the bearing yet (no brake contamination either) they would likely just put in new seals and call it done. I appreciate the advice, but that much I can do myself.

So, after much reading I think I am going to put new seals, grease test, and be prepared to do the Dr Coffee flip if required. Biggest obstacle I see is trying to get the inner retainer off to flip on a new one without destroying the ABS ring. Will try a bearing separator first, followed by angle grinder and chisel if needed. I don't think it would be a problem if the bearing splitter pushed the ABS ring a couple of mm outboard. I believe there is room for this.

I will likely tackle this in about 10 days time when schedule allows. For now the 4runner is resting parked.

 

[I_bRAD]

How are you planning to get the retaining ring back on without the press? Pipe and hammer is the only possibility I can think of, but might be a bit crude.

 

[Kanoe]

How are you planning to get the retaining ring back on without the press? Pipe and hammer is the only possibility I can think of, but might be a bit crude.

I was initially thinking pipe and hammer. But then it occurred to me my friend has a nice strong press. It is a short bench style but I think I can dangle the inboard splined end of the axle down through the base and press the retainer on with it. Not much throat is needed to get the retainer back on I am thinking.

I'm having a harder time envisioning the removing of the original retainer.