This is on my '97 4Runner.

I relocated the diff breather close to a year ago, before that I changed the leaking driver side oil seal and the passenger side oil seal, both with Timken seals although I've been trying other brands lately.

The driver side has held out but my passenger side axle oil seal keeps blowing out and I'm on my 3rd one now. I don't wheel often or at all and I drive the thing only a few hundred miles a month (not my daily driver anymoar).

So what's the deal?

 

Are you sure the diff. breather is not plugged? Also make sure the hose from the axle has no dips in it as it runs up to the breather, dips can let gear oil fumes condense and the resulting gear oil can plug the vent line. I had that very thing happen to my '85. I found this by removing the breather hose from the axle and blowing into it. Took a pretty good puff of air to blow it out, that blockage was enough to push oil past the seal.

 

did you change the bearing?

 

C.C.S. Your seal is going out b/c of some other reason. Most likely your bearing or bearing case (thing that the bearing is pressed into) is worn. Is there ANY slack at all in the bearing or with the bearing in the case?

I found on my 2000 4runner that if I replaced the case, bearing and seals it patches it up pretty good. Replacing the seal only always ended up with a leaking seal inside of a year.

Good luck!

 

It's angled pretty straight up, and the breather looks clean, I check it at every gas stop. This last oil seal didn't get 50 miles on it before it started dripping.

Can you guys elaborate about the bearing and case? I never even considered checking for play since the seal was just an in-and-out affair, so how should I go about checking and/or replacing it?

Is it located on the drum backing side of the axle shaft or the inner axle tube side?

 

Chris, mines a 2000 so it might be a little different than yours. Try to wiggle the axle in the bearing, bearing in the case (the part the bearing is pressed in) etc. If there is any play at all you need to replace the worn parts. My bearing wasn't seating in the case well, therefore moving and knocking out the seal over and over. Hopefully this fix will last at least a respectable amount of time on my 2000, on your 97 it should last forever. I've gone about 800 miles and no oil!

Here's the best pic I have of the assembly, I'll try to find some more.

Any 97 owners care to interject on differences in the two axles?

 

That is what caused mine to leak. I changed my oil seal at 186,500 because it started leaking. I thought it was just from finally wearing out. 300 miles later the bearing went out.

J-Balls picture looks about the same as my 96. If you get the bearings done you probably need to get a machine shop to do them and you will need to get several things to take to the machine shop

The bearing itself (make sure it comes with the two rings that hold the ABS ring)
The outer oil seal.
The ABS ring (I could only find this at the dealership, $60 each).

The best way I found to determine if there is play is to take the axle off and sit it down on the driveway with the lugs on the ground. Then grab each side of the backing plate and see if you can move it up and down. If you can, you probably need to replace the bearing.

 

Actually, it was the leaking seal that likely caused the bearing to go out. Why? Gear oil leaks out past the oil seal and next hits the axle bearing. Once it gets past the bearing seals, then it finally leaks out where you can see it. But all that gear oil going through the bearing washes out all the grease inside the bearing. Then you change the seal and dry ou the bearing's only source of lube and it does not last long.

 

I was changing my Tires last night and noticed oil running down the inside of the rim. So im going to tackle this tonight. So I went and bought the oil seal and the bearing figuring if the seals gone, more than likely the bearing is too. Just wondering how long of a job is it all gonna take? and is there any huge problem i may run into doin it ?

 

http://www.4x4wire.com/toyota/mainte...wheel_bearing/

 

Thanks 4Crawler!

 

I'm thinking it's the bearings

Read

 

I had read that and told that to the guy at the shop. He told me that was impossible as it was a sealed bearing. Of course he did have a steel plate in his head the size of a frisbee so I figure I should take anything he said with a grain of salt.

 

tell that guy to go get his plate polished..

 

Yes, it is a sealed bearing and guess what seals the bearing? Seals, just like the inner axle seal that first started to leak gear oil out of the inside of the axle. Over time that oil leaking past the inner axle seal works its way into the inner seal of the axle bearing, then past the outer seal of the axle bearing and the outer seal on the axle and finally you see it leaking externally into the brake drums. If the oil is not getting through the bearing, how else is it getting out, unless it is only leaking down the back side of the backing plate. I guess you could invoke some quantum tunneling affect on the gear oil molecules where they magically disappear on one side of the bearing and reappear on the other side without actually passing through the bearing itself

I saw the old bearings that were removed from my leaking rear axle and it was painfully obvious that gear oil was leaking out past the wheel bearing.

I also had the exact same thing happen on my solid front axle wheel bearings. Inner axle seal leaked, gear oil worked outwards through the birfield and wheel bearings to eventually leak out of the locking hub. When I opened up the hub, the inside was almost devoid of grease, only a thin oily film. Made for an easy bearing change since there was so little cleanup involved.

 

4crawler is right i do this repair about 5 times a month 4 times this week. I always replace the bearing

 

I know this thread is old but I've been working on my my axle seals myself on my 1999 4Runner SR5. I ordered 3 brands of seals: Timken 1960, National(Moog) 1960, and Toyota(new part#90310-50006). Comparing them side by side, the Toyota brand has more room for the axle to move without damaging the seal. The other two brands fit very snuggly on the axle with very little give. I would guess that over time with any amount of play in the bearings and hard jolts, the aftermarket seals probably get damaged fairly easily and then give out.

Check them for yourself the next time you install a set.

Also, there's a few threads touching base on the fact that the seals are set in the pocket too deeply and the seal does not ride on the spacer correctly. Measure where the seal rides with grease before you button it up.

Seal depth

 

Yeah, most machine shops will *NOT* suspect that they don't just press everything on until it butts up to the last thing they pressed on. It's pretty unusual to have air gaps between the various pressed on parts.

 

Just replaced my passenger axle seal, and bearing, also got a new breather for the axle. All done about a week ago. Not even 100 miles.

These links are the parts I got...

http://www.lowrangeoffroad.com/index...rvice-kit.html

http://www.lowrangeoffroad.com/index...ather-kit.html

Walked outside today to check, see if it's leaking, sure enough, it is... Where do I go from here? New bearing pockets?? No idea... I thought I got rid of the problem by putting in that new diff breather.

 

the seal can't be set in the pocket too deep or the seal won't ride on the spacer. Pull it out and get a new toyota seal and set it in 2-3mm less deep. Check it with grease before bolting it together.

rear-axle-seals-ultimate-information-replacement-thread-3rd-gen