willysmjeeps.com

I've noticed a bit of a drip often hanging off of the hand brake drum. I suspected that perhaps the companion flange castle nut needed tightening to seat the inner seal. When I removed the drive shaft flange, oil immediately leaked out of the cavity as if it had filled with gear oil overtime. At this point I paused to consult the manuals as it is not what I expected to find.

As per the trouble shooting section in TM9-1804B, it suggests that the oil seal is faulty and simply states to replace. Are there any other ideas or suggestions before I go about opening up the transfer case?

(split pin removed before taking this picture. It was installed)

The normal oil level is above the rear output shaft,so yes oil
Will run out when you remove the yoke.
That's why your instructed to drain the case before you start.

Simply pry out the seal and install an new one.

They make a tool for prying out seals also.

Tom

Just to be clear, you do not have to open up the case.

As Tom says, drain the fluid, remove the companion flange and drum.
You should be able to get the felt washer and seal out with a seal puller available for about ten bucks at the auto parts stores.

Just be very careful to pull only on the seal. There is a shoulder in there
that you can damage or break.

The other thing to look at is the companion shaft itself. The seal can wear a groove in it and if it's bad enough you need to replace it, otherwise the new seal won't work properly.

See Wes' photos in this thread. He shows that lip you need to be careful
of:

http://willysmjeeps.com/v2/modules/gall ... Edited.jpg

Did you seal the yoke splines too? Oil migrates out them also. Independant of the seal. That seal is hard to get out. I drained mine and removed the rear extension and tapped out the seal from behind. Like Brian said, there is a cast shoulder in there that is easily damaged. John

When you replace the companion flange, put a reasonable coating of RTV on the shaft to seal it, this will seal the shaft and prevent oil from coming out that way...

do the front the same way to keep that one dry also...

All of these steps are in the manual. TM 9-1804B and TM 9-8012, along with the civvy manual SM-1003 and the Rick Stiver's Transfer OH guide. You should reference all three, with close attention to tips and notes in Stiver's OH Guide.

Don't go overboard with sealant on the splines of the companion flanges. Just a fine film. I prefer not to use silicon sealants as they tend to ball up and block oil passageways when they eventually are rubbed off the original application surfaces. Stay with a Permatex type sealant.

From the 100's of technical illustrations and photos in my photo album @ sub-album M38 running gear.

Thanks for all of your replies on the original post. I finally got around to removing the flange today. As everything was already covered in oil, I didn't drain the case before starting so that I could observe the leak.

Here are some pictures:






I'm not sure why the outer coating in the seal turned blotchy? From what I remember it was all gold when installed. I would assume it's just wearing that way as the flange spins?

As you guys mentioned that oil permeation like this would be normal, and the seals are all brand new from the rebuild, I am thinking that I should apply the Permatex to the splines and re-assemble as I missed this step in the original rebuild.

Any other thoughts?

Yeah, those shoes are goners.

4x4M38 wrote:Yeah, those shoes are goners.

What points to that? The amount of oil contamination?

Yes Sir. I'm not sure you'd ever get that oil out of your shoes.

Now, granted, they are just the E brake shoes, but one day you might
need to rely on them to hold you without slipping.

There may be dissenting opinions, and that's fine, but if they
were mine I'd bite the bullet and replace them.

The drum can be cleaned with brake cleaner along with everything
else in there, but the shoes are porous and will wick oil out over time,
slicking up the drum and gumming up everything in there with the normal
dust and dirt.

One other thing. Be sure and look your yoke over well for wear
where the seal rides. If bad enough the seal will wear and not
seal well. There are several remedies if that is an issue.

Take care,