Rear axle seals making a mess...again

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I'm starting to prep the truck for my Rubicon trip from Jersey to the Sierra Nevada mountains and back.
Started with a rear wheel bearing inspection/service only to find the entire handbrake/inner drum assembly soaked with gear oil. The grease has washed out of the bearings and there were wear marks on both the rollers and races.

Everything, and I mean everything was cleaned and replaced on both sides with new OEM parts. New bearings, seals, lock nuts, thrust washers, even replaced the 2 bearing locknut screws.
The axles themselves had what I consider to be significant grooves where the inner axle seal (90310-35001) rides.
After a few hundred miles, I'm once again getting whiffs of gear oil smells coming from the rear.

I've read the many threads/opinions about running the FF rear without the inner axle seals (I don't want to do this), but I fail to understand how that doesn't contaminate/leak past the rear axle hub seal (90311-62002) which is clearly happening on my truck.

In any case, is there a better option other than the OEM inner rear axle seals? I probably can guess at this one.
I was considering purchasing new OEM rear axle shafts, as the splines are ever-so-slightly twisted, but the left side OEM locker version (42311-60110) seems to be difficult to source.

At this point I'm rambling on a bit due to frustration and caffeine, but I'm looking for options and still have a lot to do before June.
 
There's a seal surface reconditioning sleave that goes around the axel, where the seals ride.... SKF Speedi-sleave... I've never used them, don't know of the fit the axels we have. But you seem to be looking for ideas.
 

No idea if this is a successful solution as I have never used them.
 
Due to the hard to get short-side locking axle, I switched to RCV axles for the rear. They have a lifetime warranty, twisted splines are excluded. The hub has to be modified for extra dowel holes.

I know some axles run gear oil for the bearings and do not have that axle seal. I have no experience with this on the 80 series. Gear oil in the diff has to be high enough to lubricate the outer, and smaller bearing.

Maybe the Terrain Tamer heavy duty hub seal will stop gear oil from leaking past?

I think it is very easy to damage 90310-35001 on installation. I am hoping mine, which are recently installed, are fine. 😟

I think SKF Speedi-sleeve + 90310-35001 + Terrain Tamer heavy duty hub seal is the cheapest and fastest fix...
 
I'm starting to prep the truck for my Rubicon trip from Jersey to the Sierra Nevada mountains and back.
Started with a rear wheel bearing inspection/service only to find the entire handbrake/inner drum assembly soaked with gear oil. The grease has washed out of the bearings and there were wear marks on both the rollers and races.

Everything, and I mean everything was cleaned and replaced on both sides with new OEM parts. New bearings, seals, lock nuts, thrust washers, even replaced the 2 bearing locknut screws.
The axles themselves had what I consider to be significant grooves where the inner axle seal (90310-35001) rides.
After a few hundred miles, I'm once again getting whiffs of gear oil smells coming from the rear.

I've read the many threads/opinions about running the FF rear without the inner axle seals (I don't want to do this), but I fail to understand how that doesn't contaminate/leak past the rear axle hub seal (90311-62002) which is clearly happening on my truck.

In any case, is there a better option other than the OEM inner rear axle seals? I probably can guess at this one.
I was considering purchasing new OEM rear axle shafts, as the splines are ever-so-slightly twisted, but the left side OEM locker version (42311-60110) seems to be difficult to source.

At this point I'm rambling on a bit due to frustration and caffeine, but I'm looking for options and still have a lot to do before June.


42311-60111
 
Whatchtalkinboutwillis?
That's the right side inner, no?

RH side axle shaft w/diff lock. 👍👍

IMG_5346.jpeg
 
I was considering purchasing new OEM rear axle shafts, as the splines are ever-so-slightly twisted, but the left side OEM locker version (42311-60110) seems to be difficult to source.

You wrote left, but I think you mean right. The part number you gave is for the right side.

AFAIK, the locker and non-locker diffs use the same left axle shaft.
 
"is there a better option other than the OEM inner rear axle seals?"

There are rotary shaft seal designs/types that have multiple lips which if adapted to our axles could help decrease oil leakage even with a grooved axle shaft. Problem is getting a manufacturer to make an improved seal (design and size) to fit our rear axle shafts. IME/AFAIK all the aftermarket rear axle seals for the 80 Series all have the same simple single lip design as the OEM seal. After an extensive search (SKF, Timken, etc, etc) prior to a rear axle service I was unable to find one of the better designed multiple lip seal types with the correct ID and OD that would fit the 80 Series.


The Terrain Tamer link above refers to a type of hub seal with a unique cassette design meant to decrease wear on the OD of the spindle where the OEM hub seal can wear a groove. If that area on the spindle already has a groove the Terrain Tamer HD seal sits right over the groove and does not rotate, so it should also decrease leakage of gear oil if it makes it to the bearings past a leaking axle seal, IMO.

FWIW: I've been running the Terrain Tamer HD rear hub seals for ~20,000 miles (with OEM axle seals), no issues.


----------------------------------------------------------------------------------------------------------------------------------------------------------------

Trivia: there are more advanced rotary shaft seal designs used to prevent liquids under pressure (low, medium, high) from leaking past the seal. Our axle design would be considered a low pressure system.

Here's one example of a Cassette style seal:

Triple lip cassette seal example.PNG



Point is, if someone could find a company willing to manufacture a new (cassette type) seal that could replace the current axle (shaft) seal with multiple lips and a garter spring that might solve the issue of the OEM seal allowing gear oil to leak past. (I'm not referring to the "Eco" or other "Magic" seals, but higher quality seals designed to prevent leakage in an industrial setting).

Been discussed in the past that some people prefer to remove the rear axle seal to let the gear oil lube the bearings but you'd need to have a good hub seal, which is where the Terrain Tamer HD hub seal might help in that situation?? IMHO there is a potential problem with running without the axle seal, any contamination of the gear oil (metal shavings, dirt/rust particles, etc) might also make it into the rear bearings??
 
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You wrote left, but I think you mean right. The part number you gave is for the right side.

AFAIK, the locker and non-locker diffs use the same left axle shaft.
You are correct sir. Once again I confused myself.
I'll look at this again with a clear head when I have time.

The OEM inners don't appear to be too expensive, and I really don't see the need to go with RCVs and have the hubs machined.

I have a set of spare inners that I can experiment with and see if speedy sleeves are a possibility.
 
I also have doubts about relying on the hub seal to keep oil in the hub of axle seal is eliminated.
I've had oil find its way out past the rear hub seal after an axle seal failed. Could be that the hub seal was old and too worn to work for oil by the time the inner leaked.

I know people swear by the oil bath method.
I'm just yet to be convinced.

I think speedi sleeve is a good option, then OEM seal.
If you have twisted splines, then new axle time, which makes the speedi sleeve irrelevant. Although, the material they are made from is harder than an axle shaft. A sleeve could be installed from the get go and increase the durability of the axle
 
John,

For whatever reason, I had to do two short-cycle replacements of this exact seal (right side rear axle seal) recently - the one that fits in the tip of the axle seal against the spinning axle to contain the differential oil. It started as a normal failure on the 97 after many years. I replaced it, and a year later it leaked oil. Raplaced that one and it leaked oil a couple months later.

You know me and that my technique was correct. The only variable I noted was that the two seals that leaked were sitting in my parts box for years. One came to me from my younger brother, whom you OG's know when he moved to a 100 and mailed me leftover bits. The other was from a long ago axle job. These are so cheap I always got an extra. Factory Toyota parts. All I can figure is either age on a shelf is not kind to this particular seal, or there was a run of substandard parts.

Since you can swap this seal in about 30 minutes without even taking the tire off, I"d suggest you tilt the axle to the left by jacking it up, order a new seal (maybe even from a dealer in case a vendor has them also sitting??), and replace it. Hope you and your family are well.

Rgds,
Doug
 
I'm at 80k miles on my rear axle without the inner seals. I occasionally check the rear bearings for play, but have never found any in 80k miles. They run cool based on touching the hubs after driving on the hwy. Tires are 285s. Just finished a 14hr round trip driving 70 mph, towing a 3k lb camper with 80 loaded up as well. Haven't off-roaded this 80 much.

To throw another idea into the mix, any chance you had insufficient bearing preload and enough slack to allow the hubs excess movement? Clogged breather, seals installed backwards, damaged/dirty seal surfaces all seem like possible causes to this mystery.

Hope you get it sorted and have a great trip.
 
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You are correct sir. Once again I confused myself.
I'll look at this again with a clear head when I have time.

The OEM inners don't appear to be too expensive, and I really don't see the need to go with RCVs and have the hubs machined.

I have a set of spare inners that I can experiment with and see if speedy sleeves are a possibility.
So after digging through all my spare crap, I don't have a set of rear inner shafts. I have EVERYTHING else, but not what I need. Oh what a surprise.
I think at this point, new OEM shafts will be the quickest and easiest path forward. That should get me another 10 or so years out of them, and by that time I probably won't be able to climb in and out of the damn truck anyway.
 
I'm at 80k miles on my rear axle without the inner seals. I occasionally check the rear bearings for play, but have never found any in 80k miles. They run cool based on touching the hubs after driving on the hwy. Tires are 285s. Just finished a 14hr round trip driving 70 mph, towing a 3k lb camper with 80 loaded up as well. Haven't off-roaded this 80 much.

To throw another idea into the mix, any chance you had insufficient bearing preload and enough slack to allow the hubs excess movement? Clogged breather, seals installed backwards, damaged/dirty seal surfaces all seem like possible causes to this mystery.

Hope you get it sorted and have a great trip.
Setting the rear bearing preload on the FF rear has always been a bit of a guessing game due to the design of the lock ring and thrust washer holes.
After installing new bearings, I sequentially tighten the lock ring while constantly spinning the hub to force excess grease out. I wind up using my full weight on the ratchet and make certain the hub rotates without issue.
I very slowly loosen the lock ring until I can line up the first available set of holes for the locking screws and call it good. There is a significant difference in preload between the first set of holes and the next set, so I opt for the tighter ones.
Is that the correct amount of preload? Impossible to tell, but the next set of holes is way too loose for my taste and it's not possible to get to the tighter ones.

The bearing preload was one of the first things to come to mind which is why I replaced all the associated parts with new OEM.

Breathers are clear and I know how to install seals. I spent a considerable amount of time cleaning everything up as the entire area was covered in gear oil/dirt/poop. It was a stinky, dirty mess.
 
I know how to install seals

Since we've both been on this forum for a long time it's worth mentioning that I'm sure you know how to orient seals and many other things better than most folks but I wanted to mention seal orientation as much for posterity/other readers as for a thinking outside the box suggestion, just in case.

Did you ever experience a situation where the hubs ran up to a high temperature? It seems possible that another cause for issues like these could be overheated seals from brake drag, bearing issues, etc. At the same time I'm throwing heat out there I can also think of situations where I've overheated bearings (hubs were very hot to touch, grease thinned and smelled burned, etc.) but the seals held up so this also seems an unlikely cause unless heat was extreme. If there are other signs of heat issues (cracked linings on brake shoes, seal damage, bearing discoloration, etc.) this could possible be related to the failures you are seeing. I'm drawing at straws here but it's harder to help folks, like yourself, that have likely thought through and attended to all of the setup details correctly yet continue to see an issue.

Hopefully the new parts and setup will solve your issue.
 
I'm at 80k miles on my rear axle without the inner seals. I occasionally check the rear bearings for play, but have never found any in 80k miles.

I found play in the rear wheel bearings after removing the axle shafts, there was no play until I removed the axle shaft and then you could feel the play in the wheel bearings. And this has happened multiple times where I thought I had no play until removing the axle shafts. For the front you can check it by just lifting the wheel off the ground.
 
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