Rear Axle Seals & Bearings
 

Some background. 242k mi.

I've read just about all the threads on this topic and followed Timmy's YT video to a T. I'm aware! But dang, I'm stumped. One year ago, I did my axle seals & bearings. All OEM. I swapped the retainer rings and then reversed the ring that seats to the seal. The bevel faces outboard. Grease test showed the seals sitting in the middle of the retainer ring.

A month ago, it looked like the passenger side was leaking. The ABS rings had some gear oil on them. I pulled both sides, cleaned everything and made sure the seals were seated better in the axle housing. Again, the grease tests showed them dead center. But oddly, despite the ABS rings having some oil, the brakes appeared to have more grease than anything else. But there were signs of leaking gear oil, to be clear.

Today, i took the truck in for a free brake check. Once again, there's grease on the brake components. It doesn't appear to be gear oil. it's clumpy. i have no appearance of leakage on either back side of the dust guards/tires/components under the truck. I'm guessing that I used too much grease when I installed the new bearings. But i cleaned them pretty well before reassembling last month.

The guy suggested perhaps the hubs have worn out the axle housing. Or that I have a bent axle. I don't beat on my truck. I'm the original owner. Not a rock crawler. Most of my "offroading" consists of forest roads to get to a camp site.

I haven't checked the ABS rings yet since the work I did last month. Was I not supposed to grease the bearings before putting them on? I don't recall actually needing to press them in. They dropped in somewhat easily. I may have put them in the freezer for a bit before installing originally.

Thoughts? This shit is frankly wearing me down...especially fixing shit in 120deg heat. How should I go about finding the problem?

Thanks in advance.

In the list of the things you did to effect the repair a year ago, I saw no mention of verifying the breather was functioning.

Just last week, I examined the breather on a friend's Tacoma: it was stuck shut, no idea how long it had been that way, but no external signs of gear oil bursting past the seals.

I removed it and soaked it for a minute in a cup of boiling water. That worked.

The Breather Extension, as explained in one of Tim's videos, is A Good Thing, as Martha Stewart would have said.

I should have mentioned that. I have the breather mod up to the gas tank refill area. I tested it last month when I reseated the axle seals. It's good as new. thanks for the suggestion.

How exactly did you grease the bearings? They are sealed units with a blob of grease inside the plastic walls from the factory. If you packed grease next to the bearing somewhere it may be working it’s way out. As it gets hot the oil will seep out of the grease leaving the chunky soap which would come next.

i put grease on the outside of the bearing and the area where it seats as timmy did in the video. wondering if i used too much.

My Buddy Wei is have a similar issue. He's getting gear oil past his driver side seal and we can't figure it out. He's pulled his axle a couple times and we can't find anything wrong. The seal is mating well with the inner retainer and his breather is functioning properly.

One thing I'm starting to wonder about is the reusing of the retainers and ABS tone rings. Could gear oil be sneaking past the retainer between the axle in the retainer because it's been pulled off and pressed back on and it's no longer as tight as a fit as before? When you think about it, it doesn't seem plausible because it would have to be a pretty sloppy fit for an appreciable amount of gear oil to get past but we're running out of ideas of why gear oil continues to get past the seal.

I think I remember there being marks across the old retainer on the inside after pressing off. Score marks. It’s possible the occasional one has a groove deep enough to leak.

Maybe it’s good practice to replace the inboard one with new.

Or could be a axle seal between the outer metal part of the seal and the axle housing. Could be a distorted just a hair or scratch/score marks on the seal mating surfaces/axle housing.

That's a possibility.

A light coating of grease is recommended for bearing/retainer/abs ring installation. Are you sure it is grease and not gear oil mixed with brake dust?

I've been dealing with a similar issue. I've replaced my passenger rear axle seal 4 times now. First one I bent seating it, but didn't have a spare. Next 2 I thought were installation error. The last and most recent one I smeared axle sealant on the axle housing where the seal seats as well as the outside of the axle seal. Probably had a light gouge in the housing it was leaking past. It's been a month and its still dry so I think my problem is fixed. Verified seal placement on retainer each install as well via sharpie test.

not following you here. to my recollection, there is a seal, dust boot and o-ring:

1. inner seal that mates w/ the retainer ring (i swapped the inner and outer so my inner seal isn't riding on a previous scoring mark)?

2. dust boot?

3. the large o-ring gasket that resides on the axle housing. the entire axle assembly presses against this when you tighten the 4 bolts holding the axle to the housing?

which one of the above are you referring to?

Thanks,

Can you tell me what product you used for the axle sealant? this might be my next course of action.

it sure looks like grease, and I don't have any of the telltale signs like gear oil leaking on the rims. I suppose it could be but....

Inner seal. I would double check to make sure the whole seal itself is still sealing and square against the axle tube and check the rubber portion part of the inner seal hasn't been compromised by the axle install.

You did your research before tackling this, not implying you did a bad job. It's just one of those things that happen to everyone of us from time to time.

I went round and round with my axles seals. First two times I bought oem seals. The oem seals were the new style seal(at the time I didn't know there was two styles}. I figured the oem seals were the issue. I finally looked at a Napa seal. It was the old style. Finally swapped ends with ring that seal rest on. Problem solved. I don't know if the old style Napa seal would have worked with out swapping ends the the ring.