Rear axle seal question....

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That is only true of semi-float Land Cruiser rears. The full float rears are almost identical to the fronts, with inner and outer bearings (same part numbers as the fronts). Wheel bearings are packed with grease and don't run in gear oil.

Mine do and most of the FF 80 series that I know of run on gear oil, gave up on those silly seals longtime ago.
 
Mine do and most of the FF 80 series that I know of run on gear oil, gave up on those silly seals longtime ago.

I've often thought of doing this, but unsure of what it takes to seal them.
What is done to seal up the hub at the axle flange?
Is the standard outer seal adequate?
 
I've often thought of doing this, but unsure of what it takes to seal them.
What is done to seal up the hub at the axle flange?
Is the standard outer seal adequate?

We just use the standard hub seal and axle gasket.:meh:
 
This thread might just change my life!

Normally I would never question the wisdom of Toyota's engineers, but getting rid of this inner axle seal and the whole bearing repack process is very attractive indeed.

I have been under the impression that bearings would wear down more quickly in gear oil than in grease - is this "common sense" not so sensical? What about water entering the axle through the hub over time? And if these aren't issues, there must be more than just one advocate of ditching the axle seal, am I right?
 
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I have been under the impression that bearings would wear down more quickly in gear oil than in grease - is this "common sense" not so sensical? ...

If anything, gear oil is a better lube than grease. Without the seal, the oil can flush in and out of the hubs, replenishing the lube, grease pretty much stays in place. Flowing oil is in more in contact with the bearings, so cools, lubes better. There is little difference between the carrier and wheel bearings, and running in gear oil, carrier bearings last pretty much forever, no logic says wheel bearings would be any different.

IIRC, the schedule includes repacking the wheel bearings every 30K mi, most don't. Almost all of them we have had apart had failed inner seals, hub full of oil. With the leaking seal in place, the oil doesn't flush, likely runs at a higher level than ideal. Without the seal, maintenance is reduced to changing the gear oil on schedule and checking bearing preload (both need to be done anyway). The hub seal wasn't intended for oil, but is the same type used for oil in other places, we have been leaving the inner seal out for a longtime, some with lots of miles put on them, without issue. The failed/leaking hub seals have all been related to loose bearings, grease, oil, doesn't matter.
 
So it sounds like removing the axle seal should be fine as long as the hub seal is in good condition....

Interesting that you speculate that there's a difference between a leaky axle seal and a removed axle seal. I suppose it does make sense that you'd want good oil circulation if that's your lube. I've got a leaky axle seal but a good hub seal and no time to get parts before a big trip... maybe I'll just get in there, pull the axle seal, check preload, and call it a day.

I'm still waiting for somebody to chime in like "WAIT, NO, ARE YOU CRAZY?!"
 
The bearing grease/oil debate was floating about a couple of weeks back, bearings work fine submerged in oil. Every truck I have driven or worked on had full floaters with bearings lubed by the gear oil, common practice and has been for donkey's.

One of my rear seals had gone about I decided to sort it when I got the time, about 4 years later it was sorted, no harm done.

I had heard a rumour the oil being contaminated with grease may be a problem with diff gears? Let you know if I get any issues.

Regards

Dave
 
I had heard a rumour the oil being contaminated with grease may be a problem with diff gears? Let you know if I get any issues.

Can't see how. So long as your gears mesh well a little grease in the teeth isn't going to hurt them any. Only thing grease may lead to is clogged up passages/ports for the oil to move around. Now if you were running a limited slip differential then the grease may cause problems with the clutches.
 
The bearing grease/oil debate was floating about a couple of weeks back, bearings work fine submerged in oil. Every truck I have driven or worked on had full floaters with bearings lubed by the gear oil, common practice and has been for donkey's.

One of my rear seals had gone about I decided to sort it when I got the time, about 4 years later it was sorted, no harm done.

I had heard a rumour the oil being contaminated with grease may be a problem with diff gears? Let you know if I get any issues.

Regards

Dave


That "rumor" is that if you use incompatible grease/oils, the two will not play well with each other and will cause clumping of both and won't do their job. It MAY happen in some synthetic / dino combinations. Anything with a polyurea in it is the biggest risk. Most are lithium-based and are compatible.

I contacted Lucas Oils direct and used Lucas Red-N-Tacky 2 in the wheel bearings and used the O'Reilly's brand 85W-90 Dino gear oil in the rear diff and I made sure they were compatible before filling them. Lucas Oils advised they would be fine.

See the attached .pdf for reference.
 

Attachments

So @Tools R Us -- are you pulling the anti-splash deflectors (whatever you want to call those tin flashing pieces ~6" outboard the 3rd member) - and maybe overfillling a touch the diff?

Just wondering, since I see your mentality for when we have the rear axle flexing to each side out on trails, but highway driving seems like those deflectors in the axle shell would try & starve the bearings.

I'll take you at your word, just seems like ditching those "fling deflectors" would really help you move some fluid around for those not sealing the grease cavity.
 
I believe those anti-spash deflectors are actually a guide to help you get your axles into your 3rd member. On my 40 there was no guides and getting the long side in was a PITA. That's one of the reasons why I had a FZJ80 rear axle shortened for the 40!
 
I believe those anti-spash deflectors are actually a guide to help you get your axles into your 3rd member. On my 40 there was no guides and getting the long side in was a PITA. That's one of the reasons why I had a FZJ80 rear axle shortened for the 40!

Buddy, I'm absolutely with you on their function when stabbing axle-shafts, 11,000%.

I just was kinda doing that 'think out loud, let the masses ridicule me'-thing (so thick skin, I'm fine if Kevin berates my train of thought) - just the intarwebz, right, haha!!!

Anyhow, seriously Kevin - what's your take on those 'anti-ring gear sling, splash shields' in regards to the deletion of the inner grease seal?

Not out to pick a e-fight, how many miles has the furthest 80 gone so far on the 'no inner seals' concept? Was it your thought originally, or did you 'copy/paste' from some other source? -Really just want to track this down before I go changing anything I do- I know you get where I'm coming from, yeah?

And in reality, if it was any but you, Robbie, Christo (ok, bad example;)), Rick, Dan, Onur, or Joey - I'd flat dismiss this out of hand.
There may be others named I didn't- these are just the forum hooligans I can offhand name as people I flat know seen their share of 80 crapparoo.

You leaving them alone (axle-sling shields, not the local 'goons' I named - & really should tag), or what?

Tag edit: @powderpig , @sleeoffroad , @landtank , @cruiserdan , @beno , @NLXTACY --- this way the fellas I want input from hear I ain't just yip-yapping.

LMK your thoughts guys - esp us guys up North where fluid tries to act more like Jello ( @landtank ) -- I want this to be a discussion where us Northerners can input an idea with legitimacy something to the effect there's a good reason we have a divided grease/fluid rear axle.

Frankly I get where @Tools R Us / Kevin has a HELL of an idea for you baja runners. I just want to hear it's a Good idea for us who live up where the diff fluid is near thick as pine tar// end edit::
 
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As a seperate post, I want my last to be a way to divide where what some have EXCELLENT results mixing the grease/diff fluid - some of us in different climates may see a different result. iDK.

I want to ask it rather than assume we can all get the same result from Egypt to Hawaii, to Alaska to Florida.

At some point we need to see regional differences, yeah? --Open to ridicule, thoughts, results, yadda yadda.
 
So @Tools R Us -- are you pulling the anti-splash deflectors (whatever you want to call those tin flashing pieces ~6" outboard the 3rd member) - and maybe overfillling a touch the diff?

Just wondering, since I see your mentality for when we have the rear axle flexing to each side out on trails, but highway driving seems like those deflectors in the axle shell would try & starve the bearings.

I'll take you at your word, just seems like ditching those "fling deflectors" would really help you move some fluid around for those not sealing the grease cavity.

Have never looked for "deflectors" in the rear axle? My understanding is they are axle install aids, don't see how they would be helpful in the rear? Wouldn't matter, they don't seal, so don't prevent oil flow.

Once the oil is in the hubs, it can never fully drain back into the diff, it can only go to the level of the spindle hole. Oil isn't static, the truck turning makes the oil slosh, higher on one side of the axle,,, etc.
 
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Not out to pick a e-fight, how many miles has the furthest 80 gone so far on the 'no inner seals' concept? Was it your thought originally, or did you 'copy/paste' from some other source? -Really just want to track this down before I go changing anything I do- I know you get where I'm coming from, yeah?

Don't know the mileage, ~8-10yrs, maybe longer, including many long highway trips. Don't know how it matters, but wasn't my idea. Have worked on vehicles for many years, most full float axles are lubed this way, way common, have serviced many of them. In working on Toyota axles, most had the grease washed out, hubs full of oil, so quit putting the seals in. :meh:

... I just want to hear it's a Good idea for us who live up where the diff fluid is near thick as pine tar// end edit::

Try this, put some gear oil and grease in the freezer overnight, get back to us the next day on which is thicker? It's not like the seals are discontinued, do it how you are comfortable. I doubt that you will get a consensuses and I don't care how you do it. My advice, don't go where it's cold, completely unnecessary! :hillbilly:
 
Don't know the mileage, ~8-10yrs, maybe longer, including many long highway trips. Don't know how it matters, but wasn't my idea. Have worked on vehicles for many years, most full float axles are lubed this way, way common, have serviced many of them. In working on Toyota axles, most had the grease washed out, hubs full of oil, so quit putting the seals in.....
My advice, don't go where it's cold, completely unnecessary! :hillbilly:

Fair enough. Sounds like you have logged plenty of trips doing freeway trips where you don't tip the axle to either side or do the lateral sloshing like when out bouncing around in rocks/brush/wherever it's not paved.

I wondered on the source more as a nod to what climate this originated in, not out to doubt you or pick the e-fight, like I'd said.

More it was a mental "are we dumbing down a good/great Toyota upgrade to FF axles because it's worked in domestics all these years?"

Have a Chevy Camper Special truck here myself (454, 3/4T axles, 1T springs) - the rear is a 14bolt FF, so I've been in it (just once though), and oil-bath bearings are more the norm in petro refineries than grease-packed. So not a new concept to me either, just rare when we switch up what a certain manufacturer recommended.

Sadly, my ZIP code means we get 20-40 nights a year below freeze, so our upcoming few days of triple digit heat is a welcome but odd event. And honestly, I like living in arguably the best watershed in the States.

I get you on the whole viscosity thing - my years in the sulfuric acid plant I got used to 'proper' albeit sometimes odd moves we used to make certain machinery components (mostly pump cases & the seals on them) somewhat more reliable - sometimes we flat modded the cases or seals/retainers just so you got longer runtime between erosion / failure, so that mentality really was what was driving my questioning.
 
Bumping this thread. I’ve been having a bunch of weird issues like my driveline running smooth on the highway one way and then grumbling on the way back after being parked, both with regular driveshaft and DC.

Also my rear locker dash indicator started flickering on and off and is now on full time.

Been meaning to change the diff oil as it’s been some time since last change. Finally did it and full of grease with pretty thick stuff on the diff plug.

Inner seals were last changed at regear so 10 years and 120K miles or so. Everything is much quieter and smoother.

So I’m not going to reinstall inner seals based on this thread since I really don’t need another maintenance item.

Question is if there’s any need to go nuts getting the grease out? First thing is whether or not the diff lock sensor issue is related, meaning it’s in a position to have a grease coat on it that’s causing malfunction?

Second is outside of cleaning the grease out of the bearings/outer axle that’s accessible, anything else to do beyond running a cycle or two of cheap oil to flush it?

I didn’t know this whole issue was a thing, not looking to OCD it, just basics on effort to get to “just gear oil”.
 

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