Help with Rear Axle Leak (2 Viewers)

[Jetboy]

I really doubt jet-tard has done the repair ever, he's been a long winded idiot on this site for years. I used a claw hammer to pull the seal, took 1/5th of a second. the bearings are sealed and can easily be checked for play, do not make this a giant job, it isn't. If the bearing has play get it replaced otherwise put it back together and get on with life.

OP. You need to seriously consider taking advice from this poster. He clearly doesn't have a f'n clue what the rear axle bearing design is or how it's engineered. He did a half assed repair on his own junk and is promoting doing the same. He wrote something stupid about how centrifugal force will allow the gear lube to bypass the bearing without going through it - which makes no sense if you see how it's designed. That's simply not possible. I've explained that multiple times. This is very simple.

Anyway, take a look at how the setup is designed. The wheel bearing is a sealed bearing. It's pressed tightly into the bearing retainer pocket and onto the axle shaft. There is only one route for gear lube to leak into the rear drum - by going through the bearing. Even if the bearing weren't worn out, it now has both the wrong lube in it, and seals on both sides have failed, meaning that the lube that is now in it is going to leak out. He genuinely doesn't have a clue as to what he's writing about, or he's trying to convince you to do a half-assed repair yourself. Why he'd do that? I have no idea.

The wheel bearing is the only thing holding the axle in place. If it has a catastrophic failure, the axle shaft along with the wheel and tire can fall out - as in come completely free from your vehicle. I've had the total meltdown situation by not replacing a bearing when it was due combined with big tires and serious abuse offroad. Mine didn't actually fall out, but it wasn't far away. Had it happened on the interstate - who knows. It sucks. Fix it right the first time. Don't do the backyard hack job on it and hope it lasts a few thousand more miles. You'll be back in there replacing it again shortly. You'll end up having to pay for new brake shoes again, and another tear down. Do it right the first time.

 

[fsusteve]

you're right, he should listen to you, Mr Four Quadrants. If there is no play in the bearing, it's fine, of course the next time you replace the plugs in your motor you should prolly go ahead and do a valve job since the hood's up. You're one of those ass clowns on the internet that totally hand feeds fear to people doing any type of repair, IF YOU DON'T DO THIS, YOU COULD DIE!!!!

The reason we pack so much grease into hubs is that the spinning force known as centrifugal force with blow the grease out towards the bearings otherwise they'll run dry and develop play. I know this is tough for you to grasp but try to actually get your hands dirty instead of jerking off to gay porn before handing out advice, fxxxface.

 

[KC Yota]

Is this Facebook? Or a forum?

 

[Dini]

KC Yota click here: https://forum.ih8mud.com/95-gen-toyota-trucks/585019-help-rear-axle-leak-3.html

 

[Jetboy]

you're right, he should listen to you, Mr Four Quadrants. If there is no play in the bearing, it's fine, of course the next time you replace the plugs in your motor you should prolly go ahead and do a valve job since the hood's up. You're one of those ass clowns on the internet that totally hand feeds fear to people doing any type of repair, IF YOU DON'T DO THIS, YOU COULD DIE!!!!

The reason we pack so much grease into hubs is that the spinning force known as centrifugal force with blow the grease out towards the bearings otherwise they'll run dry and develop play. I know this is tough for you to grasp but try to actually get your hands dirty instead of jerking off to gay porn before handing out advice, fxxxface.

You've still failed to explain HOW grease passes the rear bearing without going through it. Of course you can't, but you're too proud to admit it.

Please explain how exactly you packed grease into your rear wheel bearings.

Anyway allow me to teach you a little bit about how bearings are lubricated; Sealed bearings are packed with grease. Grease is about 90% oil and 10% thickener - usually some type of metal soap. Often lithium in wheel bearing greases. The thickener generally forms fibers that create a micro-structure in which the oils will remain until acted on by pressure or heat. During the first short period of bearing operation the bearing "churns" the grease until almost all of it is deposited around the bearing cage and walls. There will be a small film of oils that lubricates the bearing rollers against the races. As the film thickness deteriorates the bearing heats up. The heat will cause some of the grease deposited around the cage and walls to seep into the bearing and re-lubricate. This process isn't 100% understood, but the general consensus is that this is how it operates. During normal operation the bearing is NOT packed full of grease and the rollers are not rolling in fluid. They have a thin surface coating and the rest of the grease is packed to the sides. If it were to churn continuously in grease, the bearing would heat rapidly and fail very quickly.

When you flow gear lube, much thinner consistency, through the bearing it will dilute the grease and wash much of it out. Most importantly it washes out the metal soaps that thicken the oils in the grease. Even if the bearing is still in great shape physically, the thickened grease is now gone. Once gone, it does not provide the function of proper heat activated lubrication of the bearings. The film breaks down or is non-uniform and discontinuous heat builds. The bearing wears until failure. Without the proper grease the bearing will not last long - it doesn't matter how good of shape it is in. If you put a brand new wheel bearing in, flushed gear lube through it, and then put it in to service, it wouldn't last long. 10k mile? Maybe 20. Not 100 or 200k miles. It will no longer be able to provide the proper surface film for the rollers.

When the axle seal is replaced, it may keep gear lube from flowing out to the bearing retainer cup. Great. No more gear lube on the brakes. Except, now the bearing isn't lubricating its self properly, and if it had gear lube leaking out, it may act to lubricate the bearing by seeping into it. Now the bearing only has whatever gear lube/grease mix is left in it. What that mixture is? Who knows? How long will that grease/gear lube mix stay in the bearing now that the seals have failed? More than likely the bearing will fail at some point in the near future - even if it were in good shape. You cannot re-pack the rear wheel bearings, nor can you evaluate what the condition of the grease is without destroying the bearing.

Most seals go bad due to wobble in the axle shaft due to the bearing already showing signs of wear or a clogged breather creating internal pressure pushing the grease out. And so replacing the seals alone is a half measure and leaves a compromised bearing in place. It will need to be re-done, most likely sooner than later. That is why it should be done right the first time. This is also why reputable shops will not replace the seals alone - they get angry customers back in 5k miles when it leaks again.

Good luck on the repairs.

And this is what a catastrophic bearing failure ends up looking like:

 

[Dini]

Cheese is riced! Will you just post the Google link where you found all that verbage instead of trying to make it look like you invented "sealed" bearings? By the way the failure in the picture you posted is not that catastrophic.

How do you know the guy in the pic doesn't change his wheel bearings every 3000 miles and just happened to hit the 3k mark in a bad spot? Poor guy didn't even have a jack or any tools.

 

[Jetboy]

You don't think an axle coming free from a vehicle is a catastrophic failure? I suppose he should just re-pack that bad boy throw a inner axle seal in and get back on the road. If only he had a jack he'd be fine. I can't imagine how that could ever turn dangerous... like if that happened at 80mph. Nothing to worry about.


If you are serious about wanting to learn more about sealed bearings, there are lots of engineering journal articles. Tribology International is probably the leading journal on bearing design, lubrication, and things of that nature. It's an Elsevier journal, so you have to have a subscription or pay per article to read them. (IMO Elsevier is a f'ing leach on society - they get articles for free from researchers, compile them then charge $ for other people to read them - but that's another topic). I'm pretty sure that somewhere like U of Oregon would have the journals in the library there to read.

 

[Dini]

No I don't think that was catastrophic failure. I've seen a lot worse. Now if I saw a bloody lifeless body/body parts hanging from the remains of a vehicle that couldn't be identified, yes.

If I'm not mistaken, the maximum speed limit in Colorado is 75 on the Interstate. Which that obviously isn't the Interstate. Now, if you have ever driven a second gen 4Runner with the 3.slow engine, nevertheless one that has been lifted and has larger than stock tires, you know that thing would have one hell of a time even reaching 80 m.p.h. Even downhill with a tailwind that 4Runner is going to have a tough time reaching 80.

Once again, I'm good on the bearings. I know plenty enough about bearings.

On a lighter note, I just changed my axle seals again over the weekend with OEM seals. My truck might have had 100 miles on the seals that were in the housing. I had the axle all torn apart doing some other work (completing my rear disc swap/abs delete), so I replaced the seals just for drill.

 

[fsusteve]

hmmm, my seals haven't leaked since replacement and the bearings seem to be fine. I just like living on the edge.

 

[ken_79-fj40]

Hate to say it Steve but Jetboy is actually right on this one. I've done this job twice. Why twice? Because I screwed up and pressed the ABS retainer ring on too far the first time so the seal didn't ride on it. Gear oil went through the bearing, I ignored it for about 2 months then the bearing started growling again. It's been fine for 10k miles now and I sold the 4Runner last month. If all you did was replace the axle seal there's a pretty good chance you'll get to find out soon how fun changing a wheel bearing is on one of these. I made a tool for it out of an old axle housing. I cut the end off and welded ears onto it to hold it in the press. The bearings are cheap and with the right tool and a press it's not a bad job. Took me about 2 hours. But if you've got ABS the tone ring and the retainers are pretty pricey. And you really can't re-use them even if you do have a strong enough press to get them off. At least I couldn't. Of course if this is your kid's Tacoma you're talking about it probably doesn't have ABS. So it would be a cheaper job but still about the same amount of suckage.

 

[Dini]

I personally replace most parts while "I'm in there" just because it's what you should do in most cases. I did not replace my tone rings, as they are not a wear part nor were they damaged during removal while doing my rear wheel bearing replacement. It's not recommended that you reuse the retainers though.

 

[drcoffee]

Possible solution to leaking axle seals

Hi guys,

I just signed up here and this is my first post. I struggled with the axle seals on my "new to me" 3rd gen 4Runner I bought for my kids. In fact in 2 months I replaced the seals 4 times until I got it right. Here is a link to a thread I started which will hopefully help others.

Posible solution for leaking axle seals