Blown inner axle seal (1 Viewer)

[94LC00X]

Hey all, I’ve got a blown inner axle seal on the passenger side of my 94 LC. It’s pissing gear oil from the birf do I’m pretty certain that’s the problem. It’s only got about 10,000 miles on a full axle rebuild so I’m a little concerned that it blew out so fast. Question is : is it ok to just replace the inner axle seal and reuse the bearings and outer seals? Or will everything in there need replacement even though it’s “new”ish?

 

[Malleus]

I assume you're referring to the front?

Yes, you can reuse the wheel bearings. Just make sure they are clean and repacked with new grease. I recommend using mineral spirits to clean and remove the old bearing grease. You can let them dry on their own, or blow them dry, just make sure you have a dryer, or desiccant capsule on a regulator, on your air supply.

Toyota lists them as "do not reuse" in the FSM, but these bearings are overdesigned for the application. As long as they have lubricant, they'll last a very long time.

Just make sure they don't have any discoloration on the contact areas and that the spindle looks OK - no nicks, grooves or discoloration.

FWIW, I'm rebuilding (not just replacing seals) my '95 front axle, due to a loose bearing preload locknut. The spindle was badly damaged, as were the preload washer and nut, due primarily to the outer bearing sliding outward on the spindle. The bearings still look new and measure completely round and in spec.

 

[SpenserAK]

Did you do the work, or someone else? Do you recall if OEM/NOK seals were used?

Typically it seems there are two main things that lead to early failure - seal was damaged on install/axle install and/or the retainer spring was knocked out of place - or, if the new seal was installed in the same position, the axle could have been worn enough in that spot to not allow for a good enough seal. I was extra careful when doing mine, and offset the seal a few mm, and it's been dry for 10k+ so far. Hopefully it's something that simple..

 

[surfpig]

Hey all, I’ve got a blown inner axle seal on the passenger side of my 94 LC. It’s pissing gear oil from the birf do I’m pretty certain that’s the problem. It’s only got about 10,000 miles on a full axle rebuild so I’m a little concerned that it blew out so fast. Question is : is it ok to just replace the inner axle seal and reuse the bearings and outer seals? Or will everything in there need replacement even though it’s “new”ish?

I would count on replacing both the seals. In my experience it's really tough to extract the seal without messing something up. Cheap insurance. The bearings should be fine. I replaced the original rear bearings a few years ago after about 160000 miles of use, but they looked almost like new. I cleaned and repacked the front ones last year (?) with about 60000 miles on them and they looked new.

 

[Kernal]

All the above plus: if the axle shafts have a deep groove (caused by the old seal) a new OEM seal won't help you by itself.

Generally the options are 1) replace the shafts 2) install a speedisleeve on the shaft (not sure how many people have tried this), or 3) install the seal so that the lip of the seal rides in a different location on the shaft.

One other maybe controversial option is to install an aftermarket seal (Marlin, Trail-gear, Terrain Tamer) that is designed to place the seal lips in a different location.

Wits End (if they're still in business) sells a seal installer tool that helps push the seal a bit deeper than flush while keeping it 90 degrees to the axis of the bore.

@94LC00X : here's a thread with photos and discussion:

Marlin Crawler vs Terrain Tamer seals for worn front axle

I have both types of seal, and its been converted to part time 4x4, axles have slight groove from seal wear, the MC seal seems a tighter fit, and looks like it will ride on a new section of axle, TT seems more flexible, but will be riding on the worn section. I am debating which one to install...

forum.ih8mud.com

Another discussion of possible causes:

Front axle seals leaking AGAIN....

Wanted to get the wisdom of the forum members on this one. I have a 1996 that I have rebuilt the front axle 2x. 1st time used marlin seals and it leaked. So I rebuilt it and used OEM seals, and now it started leaking again. I have done many rebuilds of front 40/55/60/80/minitruck conversions...

forum.ih8mud.com

Been big debates in the past on the Marlin HD seals but FWIW I installed a set of their "EcoSeals" on my 96 model over 10 years ago on grooved front axle shafts, still working.

IDK which is "best" :


Marlin link:

HD FJ80 Inner Axle Seal | Marlin Crawler, Inc.

...

www.marlincrawler.com

Trail Gear link:

Trail Safe Inner Axle Seals (Pair)

Enhance off-road performance with Trail Safe Inner Axle Seals. Prevent leaks and protect your vehicle's axle components. Shop now for superior durability!

trail-gear.com

 

[LandLocked93]

Also confirm your breather tube - and tube port on the axle itself - is clear and the valve at the end is in good shape.
Inop valve will cause pressure to build up in the diff and blow diff oil passed the inner seal.
A quick check would be to loosen the diff fill bolt and listen for pressure (or vacuum, I've heard both on mine).

 

[alia176]

Also, overfilling with gear oil can cause oil to go to the birfs. If the axle housing was tilted while the gear lube was going inside the diff, too much lube ends up inside the axle housing, then sneaks past the axle tube seal.

 

[94LC00X]

Did you do the work, or someone else? Do you recall if OEM/NOK seals were used?

Typically it seems there are two main things that lead to early failure - seal was damaged on install/axle install and/or the retainer spring was knocked out of place - or, if the new seal was installed in the same position, the axle could have been worn enough in that spot to not allow for a good enough seal. I was extra careful when doing mine, and offset the seal a few mm, and it's been dry for 10k+ so far. Hopefully it's something that simple..

a friend of mine did it in his shop which no longer exists. i bought the knuckle rebuild kit from cruiser outfitters with NOK seals.