I recently did some front end work (shocks, control arms) and now my transfer case (NP231J) is leaking. I did a UV dye test and the leak is clearly coming from the front side (see pic). I was surprised to see how forward the leak is (right next to the U joint). Do you suspect it’s the transfer case front output seal? Can the seal be replaced without removing the crossmember? Thanks for any assistance.

 

If you are talking about the x-member that supports the trans/tx case, its a few nuts and bolts, why not just remove it and support the assembly while you work on it ?

I remove seals like that with a slide hammer which has a small self-tapping screw, works every time. It may be possible to remove it with the x-member in place

 

It can be done with cross member in place, just be sure to remember to drain the T/C before removing the yoke or you might get a chest full of ATF. When you get the seal don't forget the rubber washer too, you may be able to reuse it but for 3$ its worth getting a new one. Awg is correct in the easiest way to remove it in the rig with the output shaft still there.

 

Thanks for the info. Now I’m questioning if it’s the seal leaking or is it simply oil coming through the splines and past the rubber washer prior to the nut….

Considering the leak is coming towards the very end of the yoke (and not near the seal side) any chance replacing just the rubber washer and applying a thin layer of RTV could do the trick?

thanks

 

That was my first thought as well. It's been a while since I've pulled by TC apart, but I'd give that a try.