What is this hole at the top of the transfer case rear extension housing? (1 Viewer)

[spring]

I've been looking at my t-case closely to understand where it's seeping oil and noticed there is an opening at the top of the rear extension housing.

I can't make a good picture, therefore reusing a view of someone else's t-case:

I am not sure how deep it goes but there is definitely an opening and it does not make sense to me. I wonder if something should be there and is missing.

Will appreciate any help identifying if this is normal or not.

 

[mitchjohnson000]

I think that's where the L4 or Neutral position switch is located.

 

[spring]

I think that's where the L4 or Neutral position switch is located.

Is it inside the "hole"? Or may it be that mine is missing?

I can't "look" inside the whole unfortunately - head too big

 

[Rebus Knebus]

The diagram at Partsouq lists “SEAT, RELIEF VALVE (FOR TRANSFER EXTENSION REAR HOUSING)” in this area. But I don’t know any details on the purpose of the relief valve.

 

[spring]

The diagram at Partsouq lists “SEAT, RELIEF VALVE (FOR TRANSFER EXTENSION REAR HOUSING)” in this area. But I don’t know any details on the purpose of the relief valve.

Thank you!

I did try poking it with the pencil and it only goes ~half-inch inside - so it's not a hole into the inside of the housing. It also does look like something is installed into the housing at this place - in other words, it's an opening in the housing, which has something with an opening installed into it.

 

[flintknapper]

The diagram at Partsouq lists “SEAT, RELIEF VALVE (FOR TRANSFER EXTENSION REAR HOUSING)” in this area. But I don’t know any details on the purpose of the relief valve.

Tcase is not splash lubricated.....it has an Oil Pump, so requires/incorporates a relief valve.