does clogged diff vent damage axle seals or just cause temporary leakage?

[Previologist]

Got into my drums to remove the frozen bell crank, and found gear oil, as I knew I would. Pretty much a thick layer almost everywhere.

Do I have any decent chance that the seals will stop leaking now that my vent is breathing again? Or am i doomed to doing an axle job now? I guess I can clean it all up and see what happens, but if a leaky seal never ever goes back to being a non-leaky seal, that would be good to know.

 

[GhostRing]

I was under the impression if oil gets to the drum, it has passed the bearing and is likely removing critical grease from it.

It may seem like a fair amount of work if DIY'ing it - as you do need to get/borrow some fairly specific tools, but if it's
not in danger of destroying itself immediately, you could source the parts (I used Amayama) and just have a reputable
shop do the press work and have it back up and running pretty quickly if you didn't want to deal with it.

 

[Previologist]

Yeah, there is grease under the drum too. I'm cooked.

I don't think i want the job.


EDIT: The "grease" may just be oil saturated brake dust, but it sure looks and acts like grease

 

[brillo_76]

Short answer Yes a clogged vent will create too much pressure and oil will go pass a seal. Once this occurs must of the time this damages the seal and it needs replaced. If its an original seal 20 plus year old the seal itself can just be worn enough to just to leak.


GhostRing is correct as the gear grease washes the bearing grease out of the bearing and thus the bearing will fail due to lack of lubrication once the seal is replaced. So The bearings will need replaced on the rear axles.. :-(

 

[Previologist]

Ugh. Tempting to just give up on the old rustbucket, but I already ordered the timing belt kit. Ugh. Ugh. Ugh.

 

[Riceye]

I'll be the contrarian. I have a 2000 SR5 that is my daily driver / winter beast. It rarely travels more than 100 miles from home.

I had an axle seal leak eight years back. Before I even pulled the affected axle I checked the breather. It was clogged. I removed it, got it back into serviceable condition and reinstalled. Then, I pulled the drum and axle and cleaned up the oily mess with aerosol brake and parts cleaner. Even the shoes. I put the axle in my bench vise and carefully popped out the rubber seals on either side of the bearing. It was pretty washed out from the leaking gearlube but was undamaged. I cleaned that up with the aerosol parts cleaner, re-greased with a very high quality synthetic #2 grease and reinserted the rubber seals into the bearing. I did replace both axle seals at that time just out of principle as the 4Runner had over 200,000 miles at the time. The offending seal did appear fine, though, when compared with the new one. I reassembled thinking it would at least buy me some time to formulate a better plan. That was eight years ago, and over 40,000 miles since.

I did a bumper-to bumper service last week including an oil change, driveline lube and fluid check and rotated the tires. With the wheels off I pulled the drums and found things nice and dry. Also noteworthy, I run synthetic gearlube which is more prone to leakage due to the lower pour point. The only thing that was out of place was that the breather was corroded and clogged, again. It's time to modify that with an extension hose into the fuel filler compartment.

Life in the rust belt.

 

[Previologist]

What's the contrarian part, you left the bearing in place and just cleaned and greased it there? I'm still reading through the giant rear axle seals thread
but haven't committed the parts and process to memory yet.

With 310,000 miles on my bearings though, I doubt I'll be able to get by with servicing them. Plus my oil leakage is worse than anything I've seen pictured so far. They evidently had been leaking for a while. But its good to know all the options, because suddenly becoming rich is not one of them lol

I'll be the contrarian. I have a 2000 SR5 that is my daily driver / winter beast. It rarely travels more than 100 miles from home.

I had an axle seal leak eight years back. Before I even pulled the affected axle I checked the breather. It was clogged. I removed it, got it back into serviceable condition and reinstalled. Then, I pulled the drum and axle and cleaned up the oily mess with aerosol brake and parts cleaner. Even the shoes. I put the axle in my bench vise and carefully popped out the rubber seals on either side of the bearing. It was pretty washed out from the leaking gearlube but was undamaged. I cleaned that up with the aerosol parts cleaner, re-greased with a very high quality synthetic #2 grease and reinserted the rubber seals into the bearing. I did replace both axle seals at that time just out of principle as the 4Runner had over 200,000 miles at the time. The offending seal did appear fine, though, when compared with the new one. I reassembled thinking it would at least buy me some time to formulate a better plan. That was eight years ago, and over 40,000 miles since.

I did a bumper-to bumper service last week including an oil change, driveline lube and fluid check and rotated the tires. With the wheels off I pulled the drums and found things nice and dry. Also noteworthy, I run synthetic gearlube which is more prone to leakage due to the lower pour point. The only thing that was out of place was that the breather was corroded and clogged, again. It's time to modify that with an extension hose into the fuel filler compartment.

Life in the rust belt.

 

[brillo_76]

At 310K... I suspect you have some bearing play. You can try what user Riceye did. I am glad it worked out for him. My luck is never that good. I really suspect that it really would depend on the length of the time the breather was clogged. If your catch it quick.. You could save the axel seal..

 

[19963.4lsr5]

All I did with my chronic seal leak after replacing the vent didn’t cure it was replace the seal in the axle housing.

I have a complete spare axle assembly if needed.

It’s been two years and around 15k miles. No leaks and no failed bearing…….so far. I have 75-140 synthetic in the rear.

 

[3bears]

What's the contrarian part, you left the bearing in place and just cleaned and greased it there? I'm still reading through the giant rear axle seals thread
but haven't committed the parts and process to memory yet.

With 310,000 miles on my bearings though, I doubt I'll be able to get by with servicing them. Plus my oil leakage is worse than anything I've seen pictured so far. They evidently had been leaking for a while. But its good to know all the options, because suddenly becoming rich is not one of them lol

dont forget to watch timmys video

 

[Previologist]

dont forget to watch timmys video

Yep, I started watching last night. I won't be doing any press work though. i haven't gotten to the inner seal part yet but hopefully that is within my limited abilities.