rear seal leaking AGAIN on nv5600, need a BETTER seal

[zzman]

I don't seem to be able to stop the rear seal from leaking.

I've had it changed several times but starts to leak after a couple weeks or so.

I've had the yoke changed, the u-joints changed, driveshaft balanced and installed air bags to maintain height.

There does't seem to be anything wrong with the seal when it's changed

I keep about 1 qt overfilled.



Is there a better brand seal to use?

The Dodge house changed the first one, a local drive shaft shop did the next one, then Standard Transmission did the last 2.

I wish there were a "SUPER SEAL" or something, anyone heard of anything like that?

Any one else have this problem? What is there to do?

I just added fluid yesterday, 1/2 qt low, NOT GOOD

 

[Prairie Dog]

That's strange, I'm still on my original seal at 71k and never had a leak. I imagine the shaft has been pulled and examined?

 

[KcoleKennyc]

I have about 250K on mine with no leaks. Did anyone change the bushing in the rear of the transmission? Don't believe you would get that many defective seals. It is either they aren't being installed with the correct driver or a worn bushing.

 

[zzman]

The last 2 times the whole transmission was rebuilt by Standard Transmission in Ft Worth. I think they are pretty good at what they do.

Re-build was in June and again in October 2010, about 16k miles ago.

I have added 4 qts since Oct. The leak is just enough to coat the drive shaft but not enough to leave a puddle under the truck. It doesn't seem to be getting worse. I believe it leaks more when driving at highway speeds.

I don't know what could be wrong with this thing. I was hoping someone else has had this experiance and could school me. I'll keep added fluid every once in a while, don't make much sence to change the seal every 2 weeks or so.

Thanks for your input.

 

[KcoleKennyc]

I don't know how the 5600 vents but I have had problems on other transmissions blowing seals because the vent was plugged with dirt dobbers. With all that has been done to yours without a fix, there has to be a reason. I hope you find it, I would like to know the answer to this one.

 

[smitty3500]

What has caused you to have to rebuild your trans so many times? I know many with same or more mileage then you on the original unit.

 

[Got HO?]

If NAPA has an application for it, try one. I've solved 2 repetitive leaks on my '03 using NAPA seals instead of the O. E. ones. Front pinion seal, and transfer case front seal. I must have put 10 Mopar seals in the front pinion before trying the NAPA seal 55k miles ago.

 

[Prairie Dog]

Is there a line worn in the propeller shaft?

 

[jelag]

We had a 04 that towed a very heavy trailer and we were always knocking out the rear seal in the transfer case..... We wondered that when we hit a rut or bump if the drive shaft was pounding the seal... as if the drive shaft was too long... .

We installed air bags on this truck and each time we loaded the trailer we leveled the bed by adding air to the air bags... we supplied air from the pacbrake through a simple air regulator...

Problem solved... I don't really know if the drive shaft was in fact pounding the seal but we later drove this truck another 150K miles before we sold it with no other problems... .

We always used the same parts store and I'm guessing that they were national seals...

Hope this helps...

 

[kscheffler]

How do you check the vent on the 5600 to make sure it is working. I think I saw it one time while I was under the truck it looked like a little metal cap. Do you pull it and check it off the transmission? If so how does it remove from the case body?

 

[zzman]

Transmission was rebuilt due to broken 5th and/or 6th gear. I believe I've solved that issue with the air bags.

The "propeller shaft" I guess is the yoke, it was replaced just to be sure, old one had a very small line (you couldn't feel it only see it).

The vent, that sounds like a good prospect, wouldn't the rebuilds have cleaned/or checked that? I don't where it is at. The very first time it went bad, it had completly blew off. The Dodge house said they couldn't find anything wrong with the seal but that it had come out. It was replaced with a new one.

How can I check the vent, where is it at?

Thanks guys.

 

[jelag]

Seals usually don't go bad, but they usually fail because of another problem... too much pressure as stated... a ring or worn spot on the yoke and sleeve that slide onto the output shaft... bushing failure in the transmission allowing excessive play to damage the seal... etc... .

Any good drive line shop can pull the drive shaft (propeller shaft) and check it, and than put it on a balance machine and make sure its in line (not running in an oval) and in balance... both will contribute to seal life...

I like you killed the transmission towing that heavy trailer in 6th... what I should have done was bought a 3. 73 ratio instead of the 4. 10 and every time we towed put it in 5th not 6th... . 6th just can't handle the load.....

If you were here... . I'd know just who to suggest and I'm sure they could sort it out... likewise I have a great friend in Terre Haute IN who does all my transmission work... I know him and trust him...

 

[zzman]

Took the truck back to Standard Transmission today. They replaced the seal and could not find anything or any reason why it was leaking. I drove about 80 miles back home and noticed a few drops coming from the seal. Told Standard and they said when I have the time to leave it with them for a couple days, they will FIND the problem no matter what.

So for now, I'll watch the drops.

WOW what a fiasco.

 

[rscurtis]

You might want to find someone with a smoke generator (Snap-On makes one) and hook it up to the vent or fill plug on your trans. You'll find the leak for sure in a couple minutes without even getting dirty. You'll also know when it's really been fixed.

 

[zzman]

There goes 6th gear AGAIN.............

#@$%! Well the seal is still leaking and now 6th gear seems to be cracked or broken. Once I heard the familar sound, I have kept it out of 6th gear.

I called Standard yesterday and told them I can no longer afford this transmission. He will call me today (I hope) to see if they can or have a nv4500 to replace mine. He states the 4500 (with the 5th gear nut fix) would be a good choice for my application.

I've had enough of this.



How tough is an automatic??????



Ford or Chevy??????



Maybe a want-2-B truck like a Toyota would be good?????:-laf



WOW the new Dodges cost more than my House does, this is just great.



Calgone take me awayyyyyyy Oo.