2G Transmission axle seals leaking

[Xarzor]

So I just put OEM axle seals in the transmission. Installed them with a seal installer and lubed the outer seal with transmission oil and installed the axles. Took it for a five mile drive and leaking terribly. So bad it's running down the bottom of the car.

OK back story. When I bought the car the axle seals were not leaking but I had to change the CV axles because they were slinging grease. I bought O'Reilly brand CV axles and O'Reilly brand axle seals, because I thought might as well change them not knowing when they were done last. I also switched to Redline 75-90 oil. Within a few days of doing this the axle seals started to leak. But It was just a few drops on the floor of the garage after driving to and from work. I thought it might have been the cheap seals so after a few months I ordered OEM axle seals and chaged my oil to Redline MT-90. And after five miles it's practically just pouring out.

What's the problem here? It's just a lip seal and I know I installed it correctly. I've done dozens of these on different applications with no leaks. The only thing I can think of is the diameter of the cheap CV axles are smaller then OEM.

Thoughts?

 

[spyderdrifter]

I'd buy OEM axle seals at a minimum. Better quality. Not to question your seals being installed correctly, but are you positive they are? I had this problem years ago, like back in 2008. Installed new seals, thought I did it right, even though I had never done it before then. Puked gear oil everywhere. Put in a 2nd set of new seals, again unknowingly done wrong and puked gear oil again. Got them right the 3rd time after fixing myself. Just be absolutely sure you installed them right and didn't make any small cuts in them.

 

[pauleyman]

Have you considered your front diff may have some play? Double check those part numbers too. There were two different size axles of the years. 2g is bigger. If you installed smaller seals I'm sure they would get damaged in short order. Assuming you could even get the axles through them. How many miles on that trans? Diff is worth investigating.

 

[Xarzor]

I've ordered 2 more seals from extreme psi and will have them next week. Correct me if in wrong the OEM seal should be brown in color?

This time around I'm going to test fit the seals on the axles before installing them to see if I have any fitment issues. I'm also going to check my breather.

How to I test for a bad differential? Excessive up and down or in and out play?

If the transmission has never been replaced or rebuilt just a little over 100k.

I took few minutes to see how much up and down play I have. I pushed up on the axles right at the base where it goes into the transmission. I do have play but I have no idea what the tolerances are. Any transmission guys?

 

[spyderdrifter]

Yes, the OEM seals are brown.

 

[Xarzor]

So I tore the axles out and found a few things.

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The black seal was the old one and the brown was the new one. I put a 1g seal in the first time and the second time I installed the 2g, I think. The lbck set of seals leaked way less compared to the brown set.

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The seals seem to be all the way in. I also test fitted both old seals on the axle shafts and found the blacks ones are a very tight fit and the brown ones a snug fit.
The black seal has a part number MD706433, the brown is AH2200E. Does that seem right?

The part number for the brown seals from Extreme PSI is MD742053.

 

[dwb]

Have you noticed if it's leaking around the axle shaft or the case? I do see some minor scarring on the case in that last pic but I can't tell how deep the scars go.

Is that a garter spring I see on the axle in your first pic? Is it missing from the seal you just removed?

 

[Kryndon]

At least for a 2G, the driver side seal is brown and should have a thin metal lip sticking out of it which sits flush against the case and you can also use that lip to drive it in. The passenger side seal does not have that lip and is black. Both seals have a small hole in the rubber which you are meant to position such that it faces UP. In case of over-filling the case, fluid seeps out of there through centrifugal forces.

 

[luv2rallye]

Where does it appear to be leaking - where it meets the case, where it meets the axle, or ???
Here's my factory ones (99 GST) which don't leak (although this is from the inside of the tranny looking out):

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[Xarzor]

Have you noticed if it's leaking around the axle shaft or the case? I do see some minor scarring on the case in that last pic but I can't tell how deep the scars go.

Is that a garter spring I see on the axle in your first pic? Is it missing from the seal you just removed?

The case isn't leaking that I can tell. It's definitely the seals. It didn't leak until I replaced the axles and seals the first time. Leaked worst with the last set of seals. That black ring on the axle was actually the lip from the black seal that I didn't see when I removed it.

At least for a 2G, the driver side seal is brown and should have a thin metal lip sticking out of it which sits flush against the case and you can also use that lip to drive it in. The passenger side seal does not have that lip and is black. Both seals have a small hole in the rubber which you are meant to position such that it faces UP. In case of over-filling the case, fluid seeps out of there through centrifugal forces.

I have a FWD car. Both seals are the same. It's the AWD that has two different seals.

 

[dwb]

This really is beginning to sound like an axle issue. Any chance you still have the original axles and can compare the sealing surface between the them?

I've never personally done this but I've heard you can take the garter spring out of the seal, separate the two ends of the spring and reconnect it to make the spring smaller. When you reinstall it in the seal it provides a little more pressure between the seal lip and axle.

 

[twicks69]

Per PM conversations, I also pointed out that he had the axle seal installed too far because he was not using the proper installation tool. This can cause issues. Same with the fact that he should have been either installing them clean and dry or with the equivalent of Permatex Ultra Grey / Ultra Black gear oil safe RTV sealant.

I also recommended him to check actual differential thrust play to see if the bearings have excessive endplay (they are tapered roller bearings on the differential and should be under bearing preload). Removing both axles and tossing on a dial indicator and pressing both directions on the diff could do it in-car, but otherwise, it is considerably easier to check with the transmission disassembled. Again, more work than needed if it simply a user error from installation of the axle seals.

Also for reference, the OEM 27 spline axles are 28.4mm in diameter along the smooth spot below the axle splines on the CV cup if you measure with a digital calipers.

 

[pauleyman]

At least for a 2G, the driver side seal is brown and should have a thin metal lip sticking out of it which sits flush against the case and you can also use that lip to drive it in. The passenger side seal does not have that lip and is black. Both seals have a small hole in the rubber which you are meant to position such that it faces UP. In case of over-filling the case, fluid seeps out of there through centrifugal forces.

That is for AWD only. FWD isn't like that.

 

[Xarzor]

I wanted to let everyone know the issue to the leaking was incorrectly installed seals. Finally got around to driving the car, put about 100 miles on it. No leaking! Thanks for the criticism and help from everyone! Shoutout to twicks69, you're the man! Heres a photo of the correct depth to install the seals. Do not bury the seal all the way in!

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[twicks69]

Glad my trained eye caught it and you were able to fix the problem!

 

[Jon Lane]

Are axle seals the only external openings in the 2G AWD case? My trans is leaking from the upper rear somewhere after only 1500 miles on a rebuild and I don't have the option to get under the car to look. I'd ask the builder but with only a few grand spent apparently I don't yet qualify for a simple return phone call...

 

[Xarzor]

Possible over fill on the transmission? There is a cap that looks like a mushroom on the top rear. It's a vent cap. Could be missing too.

 

[Jon Lane]

Possible over fill on the transmission? There is a cap that looks like a mushroom on the top rear. It's a vent cap. Could be missing too.

The vent cap is dry so it must be seals.

It wasn't overfilled when it started leaking. Now as I top it off it may be slightly, but I don't think that's it. The weird thing is that it doesn't leak when warm and driving - Red Line 75w140NS, which is great stuff - but it'll drip a little even 8 hours after driving it. I think the oil must sling around in the case when it's turning and only when it all resettles when the car's off it seeps out.

Are the axle seals below the sump level?

 

[dwb]

Are the axle seals below the sump level?

Yes, the axle seals are below the oil fill level.

 

[Jon Lane]

Yes, the axle seals are below the oil fill level.

Will axle seals always leak if the trans is overfilled? If so, will the level normalize once it reaches the bottoms of the seals?

 

[97egl]

Will axle seals always leak if the trans is overfilled? If so, will the level normalize once it reaches the bottoms of the seals?

No when the transmission oil is full the axle seals are submerged.

If your level is below the axle seals it is almost completely empty. Maybe 1/2 a quart at most could sit below the level of the seals. Overfilling the transmission shouldn't cause any leaks. They are vented pretty well so it wouldn't cause excess pressure. The only place an overfilled trans should leak would be the vent.

 

[Jon Lane]

No when the transmission oil is full the axle seals are submerged.

If your level is below the axle seals it is almost completely empty. Maybe 1/2 a quart at most could sit below the level of the seals. Overfilling the transmission shouldn't cause any leaks. They are vented pretty well so it wouldn't cause excess pressure. The only place an overfilled trans should leak would be the vent.

Here's the situation:

• 2G AWD manual
• Fresh gearbox rebuild with new NAPA Gold axles. Amsoil 75w90.
• Crummy black seals the guy used started leaking around 1750 miles after rebuild.
• New OEM seals professionally installed this week. Same axles. Redline 75w140. Not even 2k miles now.
• Leaked immediately.

The only common thing are the axles, so I thought maybe they were undersized. But then why did the first set of seals, which look like junk, last even longer than OEM?

This isn't my thread so maybe I should start a new one. This is strange and I can't understand it.

 

[luv2rallye]

The seals weren't put in backwards were they?

 

[dwb]

Make sure the seals are seated at the correct depth in the transmission casing. IIRC the steel part of the seal should be about flush with the outer edge of the case.

 

[Jon Lane]

Make sure the seals are seated at the correct depth in the transmission casing. IIRC the steel part of the seal should be about flush with the outer edge of the case.

The seals weren't put in backwards were they?

Think I'll collect your ideas here through the weekend and then go back to them Monday and have them check each of them.