Well the time has come to tear into my NP241DHD,  I just bought an overhaul kit, ( seals and bearings only).  I will be dropping the transfer case at some point next week / weekend.  

 

Issues are I have a random grinding when I hit bumps, either in the CAD system or in the transfer case.  Pulling the stick back to 4x4 makes the noise go away, but I not longer have a working vacuum actuator either so I don't know if it CAD is to blame as I really doubt it is able to move the collar.  

 

I also have no ability to go into N or 4l in the transfer case.  It literally hits a wall trying to push from 2wd into N, so I am GUESSING that the shifter collar inside is FUBAR, but I won't know until I tear it apart.  

 

I am gonna go to the junkyard on friday and get a replacement CAD actuator and new vacuum lines as I can't even look at them without them busting / cracking.

 

Gonna take a bunch of pictures as I go.  

Also as a side note, I finally decided to figure out exactly what axle is under my truck.  It is a 610428-4  so a 3500 1994 front axle. nice to know rather than guessing.

Me,

Wow, that isn't close.  Could it be the input bearing being in backwards?  (does this one not use the C-clip on the od to set its position?)  If it got flipped, it would pull the main shaft forward....  But there should not be enough room in the front retainer to let you get away with it.....

Good luck finding it!  I really think the true location of the input shaft is off the input bearing and front retainer.  The output shaft kind of floats, and is only limited in its movement by the output bearing.

There were two input bearing widths on the 241.  about 0.3" difference.  Is that possible?

Hag

The issue was there when I pulled the Transfercase apart, so I have to assume something wore out, or moved etc.  

 

The input bearing is correct, or at least it matches the bearing I pulled out of the case and it does use a c clip to set position.  It is seated flush and everything is happy for the bearing.  

 

I agree %100 that the mainshaft depth is controlled by the input bearing, but there is nothing between the input flange and the input bearing to allow you to set depth.  The only thing that is on the mean shaft assembly that can set depth is that bearing assembly that the main shaft sits in.

 

I set that bearing so that I now have no grinding.  I really don't think this is the correct thing to do, but it works and there is 0 chance of it coming out due to the 1/16" position movement compared to be bottomed out. 

The above picture is with the trans in 2wd so it's position is correct.  

Edited February 25, 20169 yr by Me78569

Edit:

 

big thanks to Dynamic, He pointed out that the main shaft position is held by the rear bearing and the snap ring on it in the output snout.    

 

I am gonna tear her down again and ensure that I put the bearing back fully seated, then ensure the output bearing is setting position correctly.

Could it be the pad on your shift fork that could be wear??

pads looked perfect.  

 

New pads installed anyways and the issue still exists  I am working on getting it put back together to see if the rear bearing holds the main shaft.

Big thanks to dynamic and his advice

  The main shaft position is set by the rear main bearing in the transfer case.

 

We are back together and ready to be stabbed back into the truck.  No more grinding and I now can shift to n and 4 low again.

 

Is there a vent on TC. If so where is it located. Case is oily on outside but can't tell where it's leaking. Thought maybe vent was plugged. Any thoughts?  Would it matter that I park with front pointed down hill? 

14 hours ago, Me78569 said:

Big thanks to dynamic and his advice

  The main shaft position is set by the rear main bearing in the transfer case.

 

We are back together and ready to be stabbed back into the truck.  No more grinding and I now can shift to n and 4 low again.

 

I'm still a little salty that you have the DHD  

37 minutes ago, Royal Squire said:

Is there a vent on TC. If so where is it located. Case is oily on outside but can't tell where it's leaking. Thought maybe vent was plugged. Any thoughts?  Would it matter that I park with front pointed down hill? 

Where is it leaking from?

It is wet from where halves bolt together back to output shaft seal. Kinda the whole back half is wet. I will check the bolts. May be loose 

Edited February 27, 20169 yr by Royal Squire

4 minutes ago, Royal Squire said:

It is wet from where halves bolt together back to output shaft seal. Kinda the whole back half is wet. 

Probably time for a reseal then... Once they start leaking at the mating point they don't stop. 

To answer your question though, yes they do have a vent. Where vacuum lines plug into the top of the Tcase, one of those lines is a vent that runs up to the firewall. Just find the two lines that run up there. One is vacuum, and one is a vent  

Thanks for the help 

Is there a gasket between the halves or just use silicone?

I use high temp RTV on everything.

Even on your lips. Haha. Was just putting on lip balm . Struck me as funny 

Tyler, 

 

Glad some thing on my truck makes you jealous haha.

 

I was turning that pto gear with pride when I was testing the shifting.

 

Royal,

 

Time for a rebuild.  It's very easy and you should have a nice writeup to go by soon.

I'm waiting for the write up on this...

It'll happen once I get it back in the truck and it drives

I am happy to report that I now have 2wd, 4wd high, N and 4 lo.  Transfer case is working like it should.  Seems alittle stiff, but that is likely my memory of the old broken shifter.

 

I will start building the article soon.

Awesome news man! Transmission stuff is the one thing I dare not mess with! Maybe your write up with give me the confidence I need!

I will be living I  fear for a few weeks while I wait for the transfercase to rip out of the truck.

 

Haha

Well I feel dumb...I forgot to tighten my lug nuts....not real damage other than my ego.