AW4 tail cone leak worse with new parts?

[Ecomike]

Well the 2WD 89, AW4 is leaking out the rear bushing-seal in the tail cone faster now even with a brand new, TIGHT bushing and a new seal installed in the tail cone, leaking even faster than with the old worn out parts!

The new parts came from Quadratech, the bushing was an exact match, except not being worn out, and the new seal was the right size OD and ID, but was all metal on the outside, while the old one had a rubber coating over the metal shell, new one had a felt layer inside of the spring loaded rubber lip seal on the ID, looked like a better seal, and it fit perfectly, although it was a little harder to press in.

So any ideas from the experts here why it would leak faster past the seal face? It was a slow leak before, now it leaves a 1-2 teaspoon puddle in the drive way when I park it.

 

[anthrax323]

I learned the hard way that the spring around the seal needs to be on the fluid side (inside). Really the only thing I can think of. You pre-lubricated the sealing surface too right?

 

[Ecomike]

I did not flood the felt area, just lubed up the bushing and shaft with a thin, thin layer of PB Blaster lube about 30 minutes before the final install of the shaft. There is a tube inside the tail cone that floods the bushing with Trans fluid from the pump.

The spring was inside the seal, but the rubber lip on this seal was on the outboard side of the seal assy, and the long thick felt was on the inboard side, which made sense to me, but this seal had the spring/rubber lip at the end of the seal.

Where did you get your seal?

I wonder now if the spring got loose when the shaft was slid in.

 

[Ecomike]

Guess I need to get a close look at the seal face tomorrow.

 

[Ecomike]

The old seal looked like this:

http://www.jeep4x4center.com/crown-transmission-slip-yoke-oil-seal-83504048.html

Looks like they may have sold me the wrong seal? I used this one:

http://www.transmissionpartsusa.com...sion_housing_seal_1973_on_p/760-000076403.htm

The old one looked like this:

http://www.transmissionpartsusa.com/Jeep_AW4_extension_housing_seal_1987_on_p/940-000094401.htm

Dag nab it, I hate doing stuff twice.

 

[anthrax323]

Never done an AW4 tail come seal, just my $0.02 from my axle shaft seal debacle

I'll leave further input to the others.

 

[8Mud]

One of those getting old sucks replies, I've put both styles in at one time or the other, no real issues. I just can't remember which transfer it was, early, late, Chev (241) or something else.

You can gently pull the lip down with a finger tip and feel the spring, if it is still there.

Any significant wobble can wear out the seal pretty quickly, though it does take days or weeks and doesn't happen that quick.

A finger full of bearing grease is easy insurance and certain to help you avoid frying a seal.

I know you know this, but you do need to seal the outside metal ring of the seal with silicon.

Are you sure the bushing isn't worn? Usually when the seal starts to seep, it is because of bushing wear. A new seal will stop the seep, but usually wear faster than a seal with a good bushing. The worse the bushing is, the shorter the time the seal works.

I have changed out the bushing without replacing the whole tail assembly. I was successful, but it was touch and go whether the bushing was going to move or the tail assembly was going to destruct/explode. Some kind of chemical bond between the tail assembly aluminum and the bronze alloy bushing. It did spall some when it eventually did come out, but was still tight enough when I pressed the new bushing back in. I used a giant vise to press the old bushing out IMO you get a better feel for what is happening with a vise (if you have one available that is big enough), a hydraulic press might explode your tail piece before the bushing moves.

 

[Dragonslayer]

I've done a bunch of tailcone bushing and seal changes and this is the only seal I'll use:

http://www.transmissionpartsusa.com/Jeep_AW4_extension_housing_seal_1987_on_p/940-000094401.htm

This is an exact match of the $$$ OEM dealer part and has a robust seal lip, and integral
dust boot to prevent dirt on the driveshaft from working it's way inside and degrade the
seal, itself.

Remember, the extended boot portion of the seal faces outward to the rear of the car.

I slather the seal, splines, and driveshaft yoke with white lithium grease. When I think
that I had applied too much - I put a little more on.

Be sure that the oil feed tube and O-seal has not been jarred out of position as you
position the tailcone in place.

About once a year, I'll clean the driveshaft where it enters the seal and apply a coat of
white lithium grease to help prevent the rubber boot from burning up.

 

[Ecomike]

8MUD, is that a 2WD or 4WD?

I know you know this, but you do need to seal the outside metal ring of the seal with silicon.

Neither of the two seals, old one or new one needed any sealant. The old one is 100% coated in rubber, and the new one was damn tight it nearly grennaded the housing forcing it in, so it is water-solvent tight, no sealer needed.

The bushing is brand new, less that 30 minutes of drive time on it. I replaced it because the old one was well worn and causing the leak. The drive shaft is nice and tight now, new U-joints too.

Outboard seals: The thick new one, no rubber on the outside has the spring on the outboard side at the rubber lip seal, the old one, rubber coated 100% has a lip seal on the inboard side with a spring, and a long tapered lip seal on the outboard side with no spring.

Anthrax 323 may be onto something about needing the spring on the inboard side.

And D..S is saying I should use the same style I had, the 100% rubber coated one that has two seals!!

 

[Ecomike]

I test drove it tonight, and no leak with this seal: :sunshine:

http://www.transmissionpartsusa.com/Jeep_AW4_extension_housing_seal_1987_on_p/940-000094401.htm

It went in pretty easy, almost too easy, and I used copper silicone Permatex sealant on the outside to make sure I got a good seal there.

And yes, the spring needs to be on the inside, not the outside, it seems. Had one hell of time getting the other new, earlier AW4 year style seal out I had installed recently. It did not want to say uncle:

 

[8Mud]

I put a dab of silicon sealant around the outside edge of any (all) ring seals I install. A few main reasons, one I usually manage a scratch or two while removing the old seal. which may or may not seal up with the new seal. I had a few seep around the outside edge before I got in the habit (around thirty years ago) of using the sealant on all of them and it actually acts as a lubricant when trying to slide the new seal in there. It is usually not that big of a deal to clean off old silicon.

One of those things that takes an extra few minutes and may not be necessary in most cases, just a dab of prevention. I'm also big on cleanliness, making sure the sealing surfaces are shiny clean. I'm actually a bit anal about it.

I'm also a big fan of copper paste for high temp gaskets. Real old school but it works.

 

[Dragonslayer]

Glad to read that everything worked out after using the (correct) seal that I had
recommended earlier.

I have no idea why you were using the 76403 Toyota seal on your Jeep transmission.

After trying the other types of seals from other manufacturers, the 94401 seal is the
only one I use.

 

[Ecomike]

Glad to read that everything worked out after using the (correct) seal that I had
recommended earlier.

I have no idea why you were using the 76403 Toyota seal on your Jeep transmission.

After trying the other types of seals from other manufacturers, the 94401 seal is the
only one I use.

THANKS!!!

I may have just miss read the part number right next to the right part number on the pdf file. The first one, wrong one was for the 76-86 AW4, and the one you pointed out, which works was for 87 up, was right below it in a long list.

 

[Ecomike]

LOL, it should be obvious from that photo that some serious scratches, gouges were left getting that wrong seal :gag: back out (at least I did not bust the aluminum housing, LOL) And the new one went in so easy, it was almost loose, so I did a three step seal, seal the pits and gauges first, then a second layer just before inserting the seal, then a third on the outside outer edge to make sure it stays in place. But I am not An*l about it, LOL.:wave:

Now I have a read main oil seal leak :doh:

I put a dab of silicon sealant around the outside edge of any (all) ring seals I install. A few main reasons, one I usually manage a scratch or two while removing the old seal. which may or may not seal up with the new seal. I had a few seep around the outside edge before I got in the habit (around thirty years ago) of using the sealant on all of them and it actually acts as a lubricant when trying to slide the new seal in there. It is usually not that big of a deal to clean off old silicon.


One of those things that takes an extra few minutes and may not be necessary in most cases, just a dab of prevention. I'm also big on cleanliness, making sure the sealing surfaces are shiny clean. I'm actually a bit anal about it.

I'm also a big fan of copper paste for high temp gaskets. Real old school but it works.

 

[8Mud]

LOL, it should be obvious from that photo that some serious scratches, gouges were left getting that wrong seal :gag: back out (at least I did not bust the aluminum housing, LOL) And the new one went in so easy, it was almost loose, so I did a three step seal, seal the pits and gauges first, then a second layer just before inserting the seal, then a third on the outside outer edge to make sure it stays in place. But I am not An*l about it, LOL.:wave:

Now I have a read main oil seal leak :doh:

I wish I could get the number for the seal the Mercedes mechanics are using in the rear main and the front crank. Looks to be 3/16"-1/4" wide and is made like an "O" ring. I've pulled a couple out and they looked barley worn. My guess is some old as dirt Mercedes mechanic got tired of returns and found a better solution. I've asked the local parts guy, either he doesn't know either or is playing dumb and it is a trade secret.

 

[NXJ]

Bringing this back to life.

So, the clue was (obviously) to use the completely rubber-covered (later model?) version of the seal. Is this a Timken or SKF unit, part #?

Moreover, I am having a hard time wrapping my head around the "spring" that you guys keep referring to?