Toyota steering knuckle leak

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bryson

RME Resident Ninja
Supporting Member
Location
West Jordan
Quality of grease wouldn't make it leak... something else is up.

Where exactly is it leaking from? Is it grease coming out, or gear oil?
 

OREGON85

from OREGON
So much for optimism. It's leaking out of the knuckle on the side towards the rotor, which is a problem for breaking. I ordered two new seals from Marlin. I can't believe the one Toyota seal only lasted about 9 months.
 

Noahfecks

El Destructo!
Leaking inner seals can be a sign that you have a bent/warped axle housing, especially if you find that they are wearing way too fast. Is it still stock or have you welded anything to it? Did you or someone else have a hard landing?
 

big cherokee

a.r.c fabrication
Location
layton
the marlin seals are a million times better thaan the stock stuff.

just set the two next to eachother when you get your seals.


also the marlin seals even seal with a slightly bent housing.
 

Rot Box

Diesel and Dust
Location
Smithfield Utah
The stock seals are prone to leaking even under normal use. Toyota housings are known to bend, but I doubt it will be an issue once the Marlin seals are installed.

There is a reason why Dana puts their seals so close to the carrier :-\ The distance a Toyota shaft can "walk" is quite a bit...
 
the eclosed knuckle lube debate

Theory # 1


Having said all that, here's a primer on what I think is happening with your front axle. Looking under your front end from the front bumper, the front axle housing terminates at each end in spherical steel structure. In this sphere (STEERING KNUCKLE) are your birfield joints. The sphere is supposed to be full of thick grease. The axle housing (including diff) is supposed to be full of thin gear oil. Right as the axle housing flares into that sphere there is a seal through which the actual axle shaft pierces. The seal (AXLE SEAL) keeps the two types of fluids (thick grease/thin oil) apart. Another seal (STEERING KNUCKLE SEAL) keeps the thick grease from leaking out of the sphere onto the outside of the spherical surface you can see. It is normal for there to be some weeping here, and these seals slide directly against the outside of the sphere, leaving "edges" of thick grease built up at the limits of the wheel's turning ability. Normal.

Over time, the AXLE seal wears and allows the thin grease into the steering knuckle. Here, it thins the grease out, and the grease runs out of the steering knuckle through the STEERING KNUCKLE SEALS, and also sometimes even onto the wheels via the drive plates. After awhile, the differential oil is low, and the steering knuckle is low - endangering both expensive components.

Here is where things typically go horribly awry on a LandCruiser - owing to its uniqueness and the typical ignorance of many mechanics on these somewhat rare aspects.

The lowest form of this mechanic ignorance takes this form: On the upper forward part of the steering knuckle is a square plug. This plug is only to be used to CHECK the grease level in the steering knuckle. But mechanics think this is to FILL the knuckle. It should only be used as an indicator of the grease level since the last disassembly and repack. Not for adding. Putting grease in here does not get it to the actual birfield joint - which is the place where it needs to be. So, many mechanics simply stuff grease in here and send the LandCruiser owner on his merry way thinking he's properly serviced the knuckle/joint. Unfortunately, the birfield resides in a separate chamber inside of the steering knuckle and it's still devoid of grease no matter how much you jam in that plug hole. This is the lowest form of maintenance and the cheapest.

The second form of error costs a lot of money. The mechanic properly strips down the steering knuckle and repacks the birfield/steering knuckle by pulling the axle partway (but not all the way) out. Pulling it all the way out is simply a matter of pulling it another 3 feet and laying it on the bench, BTW. Upon reassembly, they replace the seals that seem to be allowing the grease to run out of the sphere where you can see it built up as mentioned earlier. They think this seal is the problem, after all (its actually a triple seal of rubber, felt and steel designed to contain thick grease, NOT thin oil) as that's where the leak is. Honest mistake, but it's the AXLE SEAL that is causing the grease to thin and leak. The axle is reassembled, the customer pays the bill (usually around $600 per side) and they drive off with that aforementioned axle seal not replaced. Anywhere from a month to 6 months later, the continued contamination of thin gear oil causes the thinned grease/oil mix to run out that new fancy triple seal again and causes a mess and lack of lube AGAIN. Sound familiar?

So, what needs to be done is a PROPER axle service that will again last 60,000 miles before the axle seal starts to wear and leak. I doubt your birfield is toast, but will wait to hear about the "click" test to help you make a judgement. If your front diff has not been allowed to get low, the birfield is still running in oil and that's completely OK.

Back to your front shaft. There are no less than THREE grease fittings on it and most mechanics are used to zero, or one. So, it may be that you simply need someone to grease the three zirc fittings. The more I think about it, this should be done before anything else and takes someone with a grease gun about 3 minutes if they take the time to properly wipe off each fitting before filling it with grease.

IdahoDoug
 
Theory # 2

Here are a few more notes about ball-knuckles. Most MVers know that ball-knuckle joints usually leak oil. However, instead of fixing them with new seals, some folks shoot the balls full of grease. Bad move. Grease doesn’t splash around so it can’t lubricate the upper bearing, nor will it run down into the lower bearing. The same concept applies to filling the balls with heavy oil, such as 140 weight, or a product such as STP. These are too thick to splash on the upper bearing or penetrate into the lower. And, neither “fix” actually fixes anything. Ball-knuckle steering joints designed to use oil are no different from transmissions, transfer cases, axle differentials or winch gear boxes; the manufacturers knew they would leak a bit around the seals, that’s why they provided plugs to check the oil level and top it off. And, just like the other above-mentioned components, the oil in ball-knuckles should be changed when it looks dirty, becomes contaminated with water or metal particles, or simply goes bad from old age. Even if one doesn’t drive their vehicle a lot, all the gear oil should be changed about every five years.
knuckle5.jpg
 
Theory # 3

  • Chromoly FJ80 Birfields
I had some worn birfields that didn't last long with my new 40's. I busted both of them at Carnage Canyon. This was the first time I have ever broke a birfield on the trail. I've done 21 Road, Billings, even broke a rear axle but never have I ever broke a birfield! I do admit I was doing lines I have never done in my 80 before and was pushing it to the limits that day. Funny thing is the only thing that broke was the inner cage holding the balls in place. I wish they would just make those cages more beefy. Here are some pics of what you can expect to see after breaking a birfield. Notice all the gear oil has mixed with the moly grease making a soupy mess. Yes those are the steel balls inside my knuckle. The cage was diced into little bits.

The timing couldn't have been better because the next Monday Bobby Long at LongfieldSuperAxles.com finally received their new FJ80 chromoly birfields. No other vendor has ever made chromoly birfields and I wanted to be one of the first to try them out :) So here are some pictures of these bad boys side by side next to my stock birfs.
 

cruiseroutfit

Cruizah!
Moderator
Vendor
Location
Sandy, Ut
FWIW I stock the Marlin HD seals by the hundreds here in town, so if you need to get them in a hurry I've got them here and can usually get them shipped the same day you order too. Along with that I've got all the knuckle kits, wheel bearing kits, etc... in stock!
 
They have been copied and pasted, what are you confused about on the cromoly 80 post?

I began researching this subject a few months ago as it turns out there really is no need for a heavy duty seal in these units you just have to use the proper lube
which is a # 0 sodium based lube. commonly mistaken as gear oil mixing with wheel bearing grease. It is a semi fluid grease self leveling a half oil half grease if you will
I will post a add I found from australia that dicribes what land or range rovers use in thier balls incedently they call them swivels same difference though
 
lubed for life

Front Aksel Swivel Fett
"One-Shot" GENUINE Swivel Housing Grease. A semi-fluid grease which lubricates drive shaft joints, swivel pins, housing seals and protects the swivel spheres. Reinforced with solid lubricants, highly resistant to water & salt corrossion. Provides better lubrication than EP90 oil when driving, less leaks while standing. One shot packet gives "filled for life" protection. The price is for one packet and is enough for one swivel.
 

solidfrontaxle

Toyota jihad
Location
Casper, Wyoming
Not this again...



Edit: Be careful what you read on the internet when it comes to doing non-factory specified modifications. Duh, I know, but this guy got banned from IH8MUD and several other sites for some of the ridiculous misinformation he was spreading.
 
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cruiseroutfit

Cruizah!
Moderator
Vendor
Location
Sandy, Ut
They have been copied and pasted, what are you confused about on the cromoly 80 post?

Did you write them?? If not the courteous thing to do is quote those that actually said them rather than share them as you own. Might not be a big deal to you but as I'm fairly sure I know the authors of those quotes its a big deal to me.

For one, Bobby Long of Longfield fame will be the first to tell you not to run the Chromo birf in a daily-driver 80 Series. The wear characteristics of the birf are reduced compared to that of a stock birf. Regardless I was just confused as to why that is a theory for the inner axle seal failure.

I began researching this subject a few months ago as it turns out there really is no need for a heavy duty seal in these units you just have to use the proper lube

I disagree.

In my 15 years of LC knuckle experience (rebuilt hundreds fwiw), I've noted there are several major factors that cause an inner axle seal failure.

1. Wear/tear of the inner axle seal. Likely after 30+ years for the OEM design, so if your failure mode is pure wear/tear, then yes a new OEM seal would suffice.

2. Inner axle seal wear. Very often especially in high front axle miles (lots of 4x4 or full-time action of the 80), there will be a slight seal surface inclusion on the inner axle. You could speedy sleeve it (~$30 per side), you could replace it (~$50 per side) or you can run the Marlin HD seal (~$8), the Marlin seal is the clear winner imo.

3. Poor/improper knuckle alignment. Any major changes to the knuckle technically require a knuckle alignment tool, an OEM Specialty Service Tool (SST) that specifies how many shims go on the top of the axle and how many go on the bottom. This $300+ tool is not owned by many (I do have one) and without one you can only use your best judgment that you are getting the inner axle/birf aligned concentrically with the hub/spindle assemble. Otherwise you could be slightly loading one side of the inner axle seal more than the other, leading to increased wear and or an actual gap forming between the seal lip and the inner axle. Even swapping steering arms such as a high-steer swap could mess up the knuckle alignment. The Marlin HD seal can take ~5X more deflection before a gap opens. So knuckle alignment does not have to be as precise especially on non full-time vehicles. That's not to say I recommend you just slap things together, quite the opposite but at least with the Marlin HD's your procedure can be less accurate and still yield a successful rebuild.

4. Foreign object damage, such as a part from a broken birf. Again the Marlin HD would be more likely to survive having dual sealing lips as opposed to the single of the OEM design. Along with this would be inner axle failure in which the axle can actually slide into the diff far enough that the seal is no longer riding on the machined seal surface.

This is not to mention that the Marlin HD seals are far easier to install too!

I'm not a 'Marlin dealer' per say, rather when I used a set of his seals (his very first batch) there was no way I wasn't going to make those available to our customers. I like the OEM design, I'm satisfied with the OEM design but this is a case where Marlin has found a legit upgrade for the seal that results in a better offering for some customers. Your results may vary.
 

OREGON85

from OREGON
FWIW I stock the Marlin HD seals by the hundreds here in town, so if you need to get them in a hurry I've got them here and can usually get them shipped the same day you order too. Along with that I've got all the knuckle kits, wheel bearing kits, etc... in stock!

You should have put that up yesterday! Good to know for the future though. I always prefer to support local vendors.
 

cruiseroutfit

Cruizah!
Moderator
Vendor
Location
Sandy, Ut
You should have put that up yesterday! Good to know for the future though. I always prefer to support local vendors.

Well I can't put up every product I sell... would take me years and yesterday I was at the races :cool:

FWIW they are all here:
http://www.cruiseroutfitters.com/lockers.html

Next time :D

Just in case anyone else is looking, I sell all the Toyota & Samurai knuckle rebuild kits, wheel bearing kits, stud parts, and all of the individual components for all of said kits. All in stock
 
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