NP 200 Spewing Oil Everywhere

[Old_Red_Jeep]

Hey All,

So a while back I noticed that the rear output seals on my Tcase were leaking so i decided to replace them. I read on here that the Napa 21213 was the correct seal. I bought a set of those and installed them on the tcase. I had put the lip towards the inside of the case. Well, it basically started draining the oil out the shafts while driving. So I had another set and installed them with the lip towards the outside. After a quick test drive today, she's still leaking like a sieve. I don't know what the problem is. I just read that maybe the vent tube is clogged but I doubt that's it. I'll make sure it's clear anyways but before I buy another set of seals I wanted to confirm that the Napa 21213 was the correct part. Also, when you install the new seals, is it a good idea to put grease on the shaft surfaces? I hadn't done that and a friend of mine thought that that may be the problem. Right now the plan is to get another set of seals, polish the shaft surfaces, install them with some grease, check the vent tube, and cross my fingers. Any help/advice is greatly appreciated!


The brake drum gets drenched every time

[Mikel]

Is the yoke sealing surface clean? Is the ID on which the seal goes free of scratches and damage? It may be leaking from there, rather than from the lip seal area.

[Old_Red_Jeep]

would a scotch brite pad clean up mild scratches enough?

[Barrman]

Yes. Put the seal on the yoke and see if it is a snug fit. Did you have to drive the seals onto the case or they just pop right in?

[Old_Red_Jeep]

I had to drive in the seals. I made sure that they were flush when finished. I tried to tap all sides evenly so it wouldn't go in crooked

[jeepdan]

I used the National 41308 double lip, double case heavy duty seals as noted in this rebuild link.
http://blog.gieselman.com/post/NP200...r-Case-Rebuild
The NAPA 21213 is supposed to be a compatible substitute though.

Does the sealing surface on the yoke have a groove worn around it from the old seal? This can be a problem corrected by using a redi-sleeve as described in the rebuild article.

[Von]

The NP200 uses the same seals as an NP205.. don't they? I replaced one of my output shaft seals with one for a 72 GMC Jimmy NP205 a couple of years ago.
National 473468.

Sweet, you get to do a "controlled burn" on that parking brake to get the grease off.

[Old_Red_Jeep]

well, I replaced the seals with the heavy duty ones as well as cleaning up the mating surfaces and shafts. I lubed it all before putting it back in and it's safe to say that at best it's no worse than when I started this whole process. It leaves 2 drips when parked now so I'll call it good enough. I'm not keeping the drivetrain for much longer so I don't want to put a lot more into this tcase. Thanks for the help all

[brute4c]

Thanks for the update...even though it wasnt a great outcome, it helps others in the same boat to know what works and what dont...

[Mikel]

well, I replaced the seals with the heavy duty ones as well as cleaning up the mating surfaces and shafts. I lubed it all before putting it back in and it's safe to say that at best it's no worse than when I started this whole process. It leaves 2 drips when parked now so I'll call it good enough. I'm not keeping the drivetrain for much longer so I don't want to put a lot more into this tcase. Thanks for the help all

That's odd. You may want to clean the area with break cleaner to see exactly where the oil is coming from. It may surprise you...