Why have an inner seal on FF?

[Dougal]

I can't recall anyone here suggesting grease (oil + soap) is in any way a better lubricant than oil alone Dougal.

Well maybe, possibly. I wasn't quite sure what Wayne was on about, but he kept going on about wheel bearings seizing solid with oil.

So I'm afraid, much as I'd like to support a fellow kiwi in an argument, your posts here suggest to me that you're just up to your old tricks of baiting Wayne.

Well that's okay. With Astr and me in one corner and you and Wayne in the other it's one Kiwi and one Canuck* on each side. We can safely ignore the aussies, they're just making s*** up to sound important.


*Almost a Canuck, think he's near the border.

 

[amaurer]

I didn't read this entire thread because, well, I'm drunk and it seemed like there was a lot of bull**** herein...

... but anyone who thinks gear oil doesn't make an awesome (the best?) bearing lube is an idiot.

... but also so is anyone who thinks the seal on the back side of a Toyota FF hub (which is single-lipped) will retain gear oil.

 

[lostmarbles]

.. but also so is anyone who thinks the seal on the back side of a Toyota FF hub (which is single-lipped) will retain gear oil.

Yours may be single-lipped only because your BJ42 was owned by one or more of my fellow countrymen (before you plundered it from our shores). And we like to economise

Based on my 1979 BJ40, I contend that Mr Toyota used double-lipped seals there Drew. And that's something I've kept doing.



BTW ... Welcome to the fray. Why don't you stay and help throw #*##* now that you're here. (Your use of the word "idiot" was a good start.) I think alcohol helps us think more clearly and type faster

But don't think of me as a drunkard! (Heavens no!)

Today (Saturday here) is already 75% over and I haven't touched a drop. But back yesterday (Friday) where you are now - I must say I overindulged a tinsy bit.

 

[amaurer]

Tom I'm 100% that brand new Toyota hub seals - the large 4-5" diameter seal that attaches to the brake backing plate and interfaces with the race on the outside of the hub has a single lip.

I bet I have a picture, I will look...

EDIT: Oh, fxxx me, I forgot about the seal that gets pressed into the back of the hub itself and interfaces with the seal surface on the axle/spindle. That one is definitely double-lipped.

 

[lostmarbles]

....I forgot about the seal that gets pressed into the back of the hub itself and interfaces with the seal surface on the axle/spindle. That one is definitely double-lipped.

Damn. We're in agreement then (and can't therefore argue)

Here it is marked with a red dot:



(Some suppliers here in NZ provide only a single-lip seal in their kits for that application.)

 

[crushers]

Dougal, your fault is lack of actual experience.

since you have never been in the situation where you NEEDED to get home with a broken pinion allow me to state the obvious.
typical FF toyota setup.
grease in the hub bearings
seal in end of axle tube
gear lube in the housing
axle in.

pinion shaft breaks, which means you can not drive forward since the pinion rotation takes the broken off head into the ring gear and locks the rear end solid.
you can back up since the rotation pushes the head back into the pinion hole but who wants to back all the way home.
so, you pull both axle shafts out of the rear diff.
you stuff a rag into the axle housing end where the seal is, this stops the raging flow of gear lube which will contaminate the grease in the hub which will dilute the grear and make for seized bearings (yes it does happen. i have seen it more than once over the 30 years)
so the flow is stopped.
if you have a short drive with no mud, water or dirt then leave as is and drive home.
but
if you have mud, water or dirt to drive through then take duct tape and cover the end of the hub, this will allow the grease in the hub to remain uncontaminated and you can drive from North Dakota to Kitteridge Colorado (and probably much further)

non-typical FF toyota setup.
gear lube in the hub bearings
no seal in end of axle tube
gear lube in the housing
axle in.

now the pinion breaks and the before mentioned situation has developed
you remove the axle shafts which now allows the hub area to have no protection and no way to keep the gear lube (much more liquid than grease) into the hub area.
because it is a rotating mass then you can not use a plastic bag, duct tape or any other means to keep that gear lube from flowing out from around the bearings.

in other words, if you have a FF, whose great advantage over a SF is the ability to run without axle shafts in place, can not perform that function. then why even run a FF.

in the OP original post he is driving an 80, the chances of an 80 hauling a large enough load to be too heavy for a SF but okay for a FF is slim to none. FF redundant. if he doesn't have factory electric lockers or limited slip then the FF is redundant. if he switches to the full gear lube idea then the ability to run without the rear axles is redundant.

as for the benefit of running gear lube over grease, i never said that gear lube wouldn't lubricate the bearings, i said they were not designed for that purpose, the hub were designed for weight carrying and designed for grease. what i did say was that the gear lube won't stay in the bearing area and you will have a seized bearing due to no lubrication.

in the end, try it. but might be best to try it where there are no other individuals on the road.

<the entry point is the seal, Dougal, if you ever did any actual wheeling you would know this>

There are no end of ways to get home with a broken or removed half shaft. If you don't know them, it's not my fault.


And if you find water in your oil, then it pays to find the entry point.

 

[lostmarbles]

...... this stops the raging flow of gear lube which will contaminate the grease in the hub which will dilute the grear and make for seized bearings (yes it does happen. i have seen it more than once over the 30 years).......

First I'll translate Canadian into Kiwi by turning "grear" into "grease" for my reading of your words-of-wisdom above Wayne.

And then I'll add a further .

So Dougal is indeed correct!

You are indeed saying that if gear oil contaminates the wheelbearing grease it'll lead to wheelbearing seizure!

Great stuff! That enables me to side with my compatriot now..



Errrrrrr. Ooops. Damn..

More thought (which is always a curse) is now forcing me to backstep on what I've just written above ...

Just before hitting the "submit reply" button I've had a vision of where you're "seizure-experience" is originating from Wayne...
(Hmmm. Perhaps I should reword that?)

I've definitely found that when hubs are overpacked with grease, the rollers and balls (in the bearings) are forced to plough their way through bulk-grease and this can certainly cause overheating and stub-axle damage (because the inner races spin upon the stub-axle in preference to the balls/rollers fighting their way through all that grease).

And I think it is definitely possible, where hubs haven't been overpacked, for a little oil-contamination to provide exactly the same effect. In other words, I think the oil could increase the volume of the grease in the hub to produce overheating and consequent bearing/axle failure.

So now I finally conclude you're both right and we can all go to bed. (Well I will anyway cos its 11pm Saturday here.)



Edit: PS. When I've been saying "stub axle" I've been thinking of the front axle but of course on the rear axle the wheelbearing inner races sit on the ends of the diff housing instead.
Sigh... but I'm talking to myself anyway cos Wayne & Dougal must both have me on their "ignore lists".

 

[Dougal]

blah blah blah blah

<snip>
so, you pull both axle shafts out of the rear diff.
you stuff a rag into the axle housing end where the seal is, this stops the raging flow of gear lube which will contaminate the grease in the hub which will dilute the grear and make for seized bearings (yes it does happen. i have seen it more than once over the 30 years)
so the flow is stopped.
if you have a short drive with no mud, water or dirt then leave as is and drive home.
but
if you have mud, water or dirt to drive through then take duct tape and cover the end of the hub, this will allow the grease in the hub to remain uncontaminated and you can drive from North Dakota to Kitteridge Colorado (and probably much further)

Now if you have oil lubricated hubs it's all exactly the same.

Think about it.
It is impossible to get all the oil out of an oiled hub without removing the hub and sitting it down flat to drain. All of the usual methods for keeping oil in work just as well. Duct-tape, plastic bags with rubber bands. Take the wheel off, plastic bag or whatever over the hub, wheel back on to hold it in place.

Guess that's your lack of experience showing.

You say it can't be done, but it's been done by landrover owners since at least 60 years ago. But usually for reasons of broken half-shafts rather than pinion shafts.

BTW. I've mixed oil with grease many times, both intentionally and unintentionally.
Never have I seen, witnessed or even hear of such a mix seizing bearings.

 

[crushers]

actually, give it a try and report back.
not something off the web but get your hands dirty. go out to your cruiser and pull the seal from the FF rear, don't bother pulling the grease out of the bearings or changing the seal and go for a nice long drive and report back.
i am betting that the oil will contaminate the grease, both will seep out the rear bearing. the bearing will over heat and the brakes will be contaminated. THAT is what i have been saying but you can't picture it.

now, do the same test with a double lipped seal at the back of the hub and remove the grease and axle seal. go for a drive and report back. i will bet you will have issues.

then remove the shaft, plug the axle housing spindle, duct tape the end of the hub and do the same test and report back. i will bet you have gear lube draining out and the bearing will overheat.

but i doubt you will do the tests ...

 

[Dougal]

actually, give it a try and report back.
not something off the web but get your hands dirty. go out to your cruiser and pull the seal from the FF rear, don't bother pulling the grease out of the bearings or changing the seal and go for a nice long drive and report back.
i am betting that the oil will contaminate the grease, both will seep out the rear bearing. the bearing will over heat and the brakes will be contaminated. THAT is what i have been saying but you can't picture it.

No-one has suggested doing that. Suggest you read the OP followed by the answers by people who actually understood his intentions.

now, do the same test with a double lipped seal at the back of the hub and remove the grease and axle seal. go for a drive and report back. i will bet you will have issues.

This is exactly how my LR hubs run. What issues should I be experiencing?
I swapped out my original oil-lubed-hub axles for later grease-lubed-hub axles about 4 years ago (bent front housing, so I swapped both). To convert them I changed the hub seal to a dual lip spring tensioned type, pulled the inner oil seal and done.

It does appear, you are arguing against something you have never tried. Suggest getting out from behind your computer and trying this.

BTW, the whole grease and oil overheat thing.
On my vehicle I don't pre-grease the bearings going into oil-lubed hubs, I just make sure the axle oil is getting there and drive.
The Australian Army however do pack their bearings in grease before installing in oil-bath hubs. Which gives exactly the situation you claim will seize bearings. But it doesn't and they own thousands of them.

 

[Henry James the 47th]

Crusher plays the now-familiar "real world experience" card and Dougal bats it back smoothly...

 

[mudgudgeon]

actually, give it a try and report back.
not something off the web but get your hands dirty. go out to your cruiser and pull the seal from the FF rear, don't bother pulling the grease out of the bearings or changing the seal and go for a nice long drive and report back.
i am betting that the oil will contaminate the grease, both will seep out the rear bearing. the bearing will over heat and the brakes will be contaminated. THAT is what i have been saying but you can't picture it.

now, do the same test with a double lipped seal at the back of the hub and remove the grease and axle seal. go for a drive and report back. i will bet you will have issues.

then remove the shaft, plug the axle housing spindle, duct tape the end of the hub and do the same test and report back. i will bet you have gear lube draining out and the bearing will overheat.

but i doubt you will do the tests ...

I had both rear axle seals in FF cruiser leaking copious amounts of oil for most of this year due to a partly unsuccessful axle modification.

I did have issues. I got sick of being told my rear hubs were leaking oil. I had oil all over my rear tyres and spattered on my paint.

For the sake of this friendly chat, I can tell you while the axle flange gasket was leaking, I had very little oil leak through the rear seal (there is only one, and its single lipped), when I fixed the leaking hub gasket, I had oil spilling out the back of the hub and onto brakes (which didn't catch fire or smoke, just didn't stop well.
Grease turned to oily slop, bearings didn't overheat, bearings didn't seize or fail, I didn't crash into a ditch!

Two things that need to be sorted are oil tight seal at axle flange, and oil tight seal at the back of the hub.

But what would I know, I'm just an Aussie trying to sound important!







But that's not hard when arguing with Kiwis and canucks

 

[BreckenridgeCruiser]

Not that I have a horse in this race, but two things come to mind that would help me make a decision.

Toyota engineers made something that, while not flawless, had more thought, research and rationale than I have ever put into my projects.

Toyota also designed these systems to last in the harshest conditions and with not always the best service. I wouldn't mess with that. Also, they may have designed the tolerances of the system based on grease and not oil and that may be significant of a change that while I may not fly off if the road, performance and reliability may be hindered...

My conservative 2 cents in messing with Mr. T's decades of experience.

 

[roscoFJ73]

Its worked well in the 9 years Ive had Landcruisers. As already mentioned,they are capable of lasting the life of the vehicle with the correct maintenance.
Pointless trying to reinvent the wheel.

 

[ntsqd]

As for the other post where ntqsd claims he has removed his inner seal,this is all he has said


LOL Its not exactly a ringing endorsement,he hasnt done a 100000 mile trip over bad roads and come back saying how great it works.
For all we know he went around the corner and bought milk and paper and couldnt see any oil dripping down.

Actually it has about 1000 miles on it (trips towing the TrailBlazer trailer into the Mojave desert & up the coast to near Pismo, and around town) and several years of sitting waiting for me to get past other things in life and finish the engine swap. Initially there was some mild weepage at the drive flange, but I have concluded that it was the solvent in the Hylomar that I used to seal there and not diff lube. No evidence of any leakage anywhere else. I've been very conscious of that since I'm departing from the norm. Conclusive? Not in the least. Indicating a trend? Absolutely.

The seal in the back of the hub is a dust seal, definitely not oil tight.

... but also so is anyone who thinks the seal on the back side of a Toyota FF hub (which is single-lipped) will retain gear oil.

Wrong. Mine has been holding oil for several years. They were new seals, & I *think* sourced from Kurt. The bearings have how ever many Aussie km's were put on them since new or last install before SOR harvested and shipped it to the States.


Since I've only ever posted in the diesel section once before, most of you don't know me, so a short bio: Prior to going back to school for my Prototype Engineering degree I worked as a designer/fabricator/crew person in SCCA Pro Road Racing and Vintage Road Racing & sports/touring car restoration. I've also worked in ultra-high vacuum (you partially owe your flat screen tv's to the R&D vacuum chambers that I assembled). I started my off-road "career" in a rock crawling fiberglass 'dune buggy' in 1985. Those that scoff at that concept are lacking a sorely needed education. To keep up with it's one wheel drive and 31" tires with a 4x4 usually required at least 33's, two lockers, and a talented driver.
Since earning the degree I spent 2 years designing brake system components at wilwood and ~8 years at APT/Ecomotors doing engineering support tooling & fixtures for R&D projects on the small engine dyno and turbocharger hot gas test stand. Along the way I've been race crew in every form of 4 wheeled racing except LSR and oval track. I'm currently crew on two desert race vehicles and used to be a member of LocosMocos, but after a brush with some of the border craziness I quit crossing into Baja.

So the why of this is that I am using an NP241 t/c in my engine swap. That requires a centered diff. Since the SF axle kilt itself dead (pics somewhere early in my build thread) and I found that two axles + bearings and seals would run almost as much as a SOR FF assembly, AND I have near hatred of c-clips and SF axles, going FF was a no-brainer. Moving a FF diff to center will be a bit easier than moving a c-clipped SF diff to center.
Eliminating that outer seal makes getting new drive axles made a lot simpler and less costly. It also eliminates the potential for a circular score line, which is a stress riser on an already - at times - highly stressed region on the axle shaft. My current OE shafts have this score line. The lip of the seal has worn a groove in the shaft. We all see this all the time with lip seals, nothing new there. But the seal in that spot was. None of the US domestic FF axles have such a seal, at least not any that I know of. Since I could see the reason why and had examples of it not being needed I decided to try it without. It's an experiment, but one that I think has a high potential for success or I'd have found another way.

Since grease is essentially a high tech mixture of oil and soap I'm betting that the oil was doing the lubrication and not the soap. The soap just holds the oil in place so that it can do it's job.

 

[roscoFJ73]

Those that scoff at that concept are lacking a sorely needed education.

LOL You still havent proven its a long term and viable concept. What happens if I hole the housing 100 miles from anywhere?

. None of the US domestic FF axles have such a seal, at least not any that I know of.

Lets face it,US domestic trucks are a fairly soft truck.Take them offroad for any length of time and they start falling to bits pretty quickly.They are good at towing big loads at high speed ,but that about it.
Toyota Landcruiser is probably the most used vehicle in all the hell holes of the world. I have taken my Landcruisers into some pretty remote and inhospitable places. I would not rely on any other vehicle.Nor would I modify it just because someone else does it different and its most likey done as a cost saving measure.
Ive never seen groove marks on the axles of the 3 landcruisers I have owned

Since grease is essentially a high tech mixture of oil and soap I'm betting that the oil was doing the lubrication and not the soap. The soap just holds the oil in place so that it can do it's job.

So we know it does its job,why change it?? Toyota have stuck with it through many models while changing many other things.

 

[Dougal]

LOL You still havent proven its a long term and viable concept. What happens if I hole the housing 100 miles from anywhere?

Do whatever you like. Throw a hissy fit, cry, scream, call a tow truck or just patch the hole and drive home.

That problem and it's solution is no different in any way to running with greased hubs. It's been covered already in this thread.

If you are only happy using toyota genuine parts and washing your vehicle with toyota approved soap lest the sky fall on your head. That's fine.
Some of the rest of us have the skills and knowledge to do better than the "one size fits all" which comes out the toyota factory.

To put it another way: "Those who say it's impossible should not interrupt those doing it."

 

[lostmarbles]

Nothing in this thread has given me any reason to change what I said at the very beginning either:

In my opinion, the further away you can keep oil from brake linings ... the better.

And I don't think grease is significantly-enough inferior to "pure oil" to be capable of noticably reducing wheelbearing life.

Hence I support retaining the inner seals on the rear axle.

It is of course even more important to have those seals in good nick on the front axle because the swivel seals (wiper-ball-seals or whatever you call them) on the steering knuckle housings can't hold oil and will readily leak it out all over your wheels (and brakes).

My 2c.

 

[Dougal]

Nothing in this thread has given me any reason to change what I said at the very beginning either:

I don't think anyone has been arguing about those either. Certainly factors to consider.

But if you were to claim that oil/grease mix seizes bearings, the sky would fall, a bus-load of Nun's would catch fire or you wouldn't be able to get home after termites ate through the 1/4" plate of your diff housing.
Well then the discussion would continue.

I am surprised the toyota swivel seals can't keep oil in. But given that toyota swivels generally aren't replaceable, being able to keep the surface in good enough condition to retain oil could be a struggle.
Landrover went from oil to black gooey CV grease in their swivels about 15 years back. The grease is truely awful to work with, I also converted the swivels in my later axles to oil bath.

 

[snowboardonsnow]

If I may, first off all ya'll are way smarter then me but I believe what crushers was saying about the bearing seizing (correct me if I am wrong) when running oil lubed hubs they may tend to leak, normal people (specially american idiots) may never check the oil level/refill/fix the seals, and this would lead to running dry bearings which will lead to seized bearings.

I could be wrong but thats all I can guess from bearing seizing in oil... other wise how the heck would it seize? I think his argument is them running dry.......