Thread: passenbger side axle seal STILL LEAKING FFS!

I replaced my CV joints about 2 weeks ago. After this, I saw leaking from the passenger side CV seal.

I popped the CV to see that I'd popped out the seal spring. So, I took out the old seal and replaced it.

I'm now on my third new seal and I'm still getting leaking.

I did not gouge the bore of the diff where the seal sits. It's pristine. I even took a cloth wheel on my dremel and brake cleaner on a q-tip to clean it before placing the last seal (a seal I coeated with RTV before installing - just in case).

My question: I lubed the axle before placing in the bore. This is the way I've always seen it done (to make sure the axle slides in and doesn't nick the seal). Will this cause leaking? In other words, must the seal/axle surface be dry in order to form a proper seal?

I've checked everything I can think of:

1) the axle itself looks perfect - I don't have a mic at home or I would make sure the diameter is fine
2) the diff housing is not at all gouged
3) I installed the seal with a proper tool (a mag light with the lens removed - the diam was perfect to press in the seal)
4) the seal is a moog seal, and looked perfect (no molding defects or whatever)

I'm down to either the lubed axle seal (non dry) permits seeping or the new CV has the wrong OD. Since it fits perfectly in the bearing, I don't imagine that's the issue.

What else could I be missing?????

another question....

I just had this apart again (I could prooly remove the CV joint in my sleep now) and noticed that the cup of the axle is about 1/2" away from the seal. This puts the sealing surface of the seal itself barely on the shaft.

I also still have the OEM seal rubber part. It's much tighter on the axle than the new one (though the new one has an interference fit so it should seal).

So - is the cup usually that far away from the seal? I'm sure the c-clip is engaged as I can feel/hear it click and it's a ***** to remove once enganged.

The seal I'm using is this one:

More Information for TIMKEN 3543

Yes I get a click. After it's all the way in, I have to pull with everything I have to get it removed (and it pops out rather than slides).

Here is a picture of it installed - see how far away the cup is from the seal? Is this normal? I'm beginning to wonder if the axle I got (reman from Checker) is the right one.

ImageShack® - Online Photo and Video Hosting

One last thing....

I'm worried that the three seals I have put on this are the wrong seal.

They fit perfectly in the diff and seem like they should seal the axle. But, they're about .050" LARGER ID than the OEM seal.

The old seal was tight around the axle shaft while the new one is merely an interference fit tight.

I have the original OEM seal and the three new 3543 seals in front of me. They are basically the same ID (within 0.010" - it's hard to tell as the OEM seal is not inside its cage so the diameter is not perfectly consistent).

When I installed what's left of the OEM seal on the shaft, it was a MUCH tighter fit than the new seal. And, that's without the spring. The newer seal is more flimsy (maybe that's because the older OEM seal is more brittle after 15 years, but it's not at all splitting and still very pliable - it's just more rigid than the new seal).

The OEM seal has a black seal while the new ones all have dark orange colored seals.

The sealing lip of the new seal is a fine edge (the corner of a triangle) and the OEM seal has a much flatter sealing lip where the surface of the seal would contact the axle over more area.

Bottom line: the THREE new seals leak more than the OEM seal did with the spring knocked out of it.

I'm getting DELCO seals tomorrow (well, my wife is, for me, while I'm @ work).

I'm hoping this cures the issue as I'm PISSED that I spent a whole weekend changing the oil pan (any of you who have done that know what a royal pain in the ass it is) to CURE an oil leak (the bottom of my engine is BONE DRY) just to have this stupid axle seal leak like a sieve.

I've had the CV out ten times in the last two weeks. I can take it apart with my eyes closed and have it pulled in about ~20 min.

It's just so frustrating to see the oil pan that I could eat off of next to a soaked diff cover. Oh well, a new seal (4th time) is certainly easier to fix than a faulty oilpan gasket. That would probably make me postal.

I think I found the source of the leaking.

The problem is that the OD of the CV changes to slide into the inner bushing/bearing. When it necks down, it's filleted. This rounded shoulder is where the sealing surface of the new seal is trying to seal. Basically, the larger OD of the axle isn't deep enough into the seal to stop leaks.

So, I can't ram the new CV in any further. The shoulder is more or less flush against the bushing (I removed the seal and put in the CV to confirm).

I spent about 1/2 hour measuing the remnants of the OEM Delco seal and the three new 3543 seals. The OEM seal has its sealing surface very slightly further out from the diff cover than the new 3543 seal (about 0.060" according to my calipers).

This additional inset of the sealing surface along with the radiused shoulder is causing the leaking.

Two questions:

1) Is the output support support (passenger side differential) a bushing or bearing? It looks like a bearing to me but I cannnot for the life of me get the inner 'race' to turn on what I presume to be its rollers. I haven't wedged anything in there to try and turn it as I don't want to break it or anything.

2) Are the shoulders on these CV joints typically filleted like that? If it stepped up rather than gradually radiused up in OD, this seal would work fine.



I WISH I still had the OEM CV to measure. I have a feeling that the larger shaft portion on it extended further into the diff housing making the seal more effective.

Right now, the new seal is basically trying to seal around the shoulder fillet that has a much smaller and non consisent (along the axle axis) OD. No wonder it leaks....

If I don't fix this soon I'm either going to go crazy or my wife is going to kill me for spending so much money and time on my "stupid car".

I re-re-re installed the CV in the diff without the seal - the filleted shoulder is more or less flush with the bushing. It can't be pushed in any further. Moreover, this alleviates the concerns I had re: wrong/mis machined CV (as fara s the relationship between axial depth and diameter).

I also scrubbed the entire diff housing with brake cleaner to make sure I wasn't missing a crack or something else that would be the source of the leak - nothing there.

I'm down to hoping that the 0.060" depth difference in seals between OEM and aftermarket solves the issue.

I will know in a couple of days.

I wil post pics of installation today hopefully. Thanks for the help guys!

New OEM seal (SKF re-brand).

Dry as a bone.

I have lots of pics I will post this weekend.

The OEM seal came with a small note in the baggy from Delco saying that it's a new improved design (albeit the same as the one that was in my car dating back to 1998) that puts the seal 2mm further up the shaft of the axle.

This reconciles with what I had measured @ 0.060"

Who would have thought that 2mm in AXIAL POSITION (not OD) would mean the difference between a leaky mess (6" daily spot) and no leaks whatsoever.

The other good thing about this is that it got me off my ass to replace my ball joint (the boot was torn). Not nearly as bad of a job as I thought - 3/8" drill bit, grinder, driftpin, and ~45 min it was done.