I just replaced the front driver side hub, because of a humming noise when driving, and all was going well. Took it for a test drive and the noise is now gone. Great.
But lately I've been hearing a type of rattle/light clanking noise from underneath, around the transmission area. Hoping it wasn't the transmission. So I crawled underneath to check for maybe a loose bracket or exhaust. And found this.
An open/missing something on the NP246 transfer case. After some research I've found that it is a "Clutch lever pivot pin". There are two of them, and this one is missing. I'm guessing it has worked it's way out and is lost forever.
I have checked and cannot find one anywhere.
Would anyone happen to know where I can get a replacement? It looks like it has lost fluid and I plan on draining out the old and putting in new. I'm hoping that this is where the new noise is coming from. If not, then the transmission may need rebuilt.

 

Looks like an entire drain plug to me. Be it drain hole or something else I would not drive that vehicle anyplace, otherwise you risk more damage then you may have now.

And let me clarify something that might help New Process (NP) is now called New Venture (NV), so if you use that to search for the part, it may come in handy. Please do not drive with that kind of opening in your transfer case. I've no doubt that you can hear a noise, since it appears to me that someone didn't put that part in properly and you have major fluid loss.

If you had any work done there, that you did not do, you may be able to force them to install the entire NEW transfer case or face a lawsuit. Keep any paperwork handy to turn over to the attorneys as this matter can be settled out of court, if you can show proof of negligence. It will be cheaper for them to repair/replace then a lawsuit, trust me.