5 Knuckle Jobs Later... Still Leaking (1 Viewer)

[ARCHIPEEP]

Sorry for another axle seal post, but I've been through as many as I could find and have tried everything in the forums with no success.

A few years ago, I decided to upgrade my diffs to 4.88 for my 35" tires. While I had it all apart, I went ahead and upgraded the front axles to RCV's.

Not more than a few months later, my birfields were leaking and the grease was gear oil soup. Did the knuckle jobs and a few months later same thing. I would literally have to do a knuckle job every 2 trips we took. This year, it seems like every trip we take we end up with a knuckle job.

Here's whats been replaced:
Replaced the diff with a lightly used unit from a friend that only wheeled it for maybe 10k. Already had the 4.88's on it.
New RCV Axles and birfields
New OEM seals
New bearings
New spindles and spindle bushings from Cruiser Outfitters
New tie rod ends
New upgraded lower knuckle studs
New preload shims

The last item I can think of is to check the alignment of the birfield in the housing. I may have removed the lower knuckle shim the first time I did the knuckle job, but that was so long ago, I don't recall.

One other thing I noticed the last time I did the knuckle job was that my birfields didn't seem to move very smoothly, almost as if they were kind of tight. I don't recall how they felt when I first put them in, and I've seen a few posts of people saying that this is normal, but seems wrong.

Our trips are light off road, mostly desert. Nothing like the Rubicon.

Any guidance would be appreciated. I'd love to take a trip and not have to do another knuckle job for at least a year or two.

 

[BILT4ME]

Sorry for another axle seal post, but I've been through as many as I could find and have tried everything in the forums with no success.

A few years ago, I decided to upgrade my diffs to 4.88 for my 35" tires. While I had it all apart, I went ahead and upgraded the front axles to RCV's.

Not more than a few months later, my birfields were leaking and the grease was gear oil soup. Did the knuckle jobs and a few months later same thing. I would literally have to do a knuckle job every 2 trips we took. This year, it seems like every trip we take we end up with a knuckle job.

Here's whats been replaced:
Replaced the diff with a lightly used unit from a friend that only wheeled it for maybe 10k. Already had the 4.88's on it.
New RCV Axles and birfields
OEM seals
New spindles and spindle bushings from Cruiser Outfitters
New tie rod ends
New upgraded lower knuckle studs
New preload shims

The last item I can think of is to check the alignment of the birfield in the housing. I may have removed the lower knuckle shim the first time I did the knuckle job, but that was so long ago, I don't recall.

One other thing I noticed the last time I did the knuckle job was that my birfields didn't seem to move very smoothly, almost as if they were kind of tight. I don't recall how they felt when I first put them in, and I've seen a few posts of people saying that this is normal, but seems wrong.

Our trips are light off road, mostly desert. Nothing like the Rubicon.

Any guidance would be appreciated. I'd love to take a trip and not have to do another knuckle job for at least a year or two.

What torque are your wheel bearings set to?
Have you had the trunnion bearings replaced?

 

[ALX4X4]

inner axle seals done ?

 

[ARCHIPEEP]

All new seals. All new bearings.

Set the torque of bearings to factory spec, then tried 10lbs then tried 20lbs.

 

[1973Guppie]

What axle seals are you using? Full time or part time 4wd? How much gear oil are you putting in the axle, it can be overfilled causing a leak. If you are using brand new RCV's the seal surface should be good. I would get the OEM alignment tool to ensure the axle is being placed correctly. I believe trail tailor sells one. Sounds like your shims are wrong. Are you using any shims at all? Another thing to consider is a bent axle housing. This would throw off the concentric nature of the axle where it sits on the seal. Pull the whole thing apart without a seal and install the axle into the housing and you should be able to see if it is off. Good luck.

 

[ARCHIPEEP]

Oem seals. Sumos this time. Used Toyotas last time. Full time fwd. Overfilled may be possible., but doubt it. Gonna try adjusting the axle alignment. Got a buddy with the sst. Seems strange to me that such thin shims matter so much when the axle seals have some flex.

 

[ajax1]

Not saying anything but you are sure you are not damaging the seal when installing or knocking the small spring out of the back? I always pack little moly on the spring to help hold it. Also if your shims are gone, that is a issue as now the knuckle is not centered to the axle. Enough to cause that I can’t say. The birf should rotate around in the knuckle no problem. If the breather is clogged that can blow out the seals as well

 

[ARCHIPEEP]

Yeah, I’ve checked the seals after I pull the axles. Springs have been in place.

Breather is clear.

 

[landtank]

Check the breather for the axle. As the axle heats up you could be pressurizing then axle slightly.

 

[1973Guppie]

Install that axle in the ball when it's all broken down so you can see where it rides in the housing, these axles do get bent, has it always been this way since you have owned it? You def needs shims, they are there for a reason from Mr. T.....

 

[BILT4ME]

All new seals. All new bearings.

Set the torque of bearings to factory spec, then tried 10lbs then tried 20lbs.

Many of us have finally settled on 35 LB-FT for the inner nut and 45 LB-FT on the outer nut for the wheel bearings.

 

[1FZj80]

go with the heavy-duty inner seals from Marlin

HD FJ80 Inner Axle Seal | Marlin Crawler, Inc.

...

www.marlincrawler.com

 

[SpenserAK]

^ If I’m not mistaken, those are known to not work as well on full time trucks, and OEM is most recommended.

 

[Broski]

^ If I’m not mistaken, those are known to not work as well on full time trucks, and OEM is most recommended.

^^^^ this

 

[Broski]

Bent axle housing or clogged breather

 

[Box Rocket]

What Broski said. My money is on a bent housing. And, don't use the Marlin seals. They do not work nearly as well as OEM seals.

 

[ARCHIPEEP]

Yeah, not gonna use the marlins.

Housing is fine. No issues till I did the first knuckle job. I don’t wheel it hard at all. Mostly desert trips.

Breather is clear. I blew air through it when the seal was out.

 

[Broski]

Maybe you just need to wheel it harder

 

[SmokingRocks]

Do your spindles have the brass bushings in them? That was my issue.

 

[vegasfj40]

So if everything was fine before you did the job, the housing is probably fine. I would maybe mic the diameter of the new axles vs your originals. Axle fluid is getting past the seal. Have you tried going back to your original Birfs? Also, are both sides leaking at the same rate?