transfer case leaking from fill plug

Hi there fellow Navarians,

I have a problem I am not really sure why its happening etc.

I noticed in a general under body inspection/clean/blow out that the transfer case was leaking from the fill plug. I thought I would take the plug out clean it etc and re-seat it thinking there must be sand or grit stopping it from sealing properly. When I took the plug out oil poured out of the hole. Is this normal for the oil level to be above the fill plug hole? Does it drain back from the gearbox or something? I quickly screwed the plug back in and have cleaned it off as best I can. The car was on level ground at the time of inspection so this one has me stumped.

Any help appreciated.

PS: I did change the oil 6 months ago with the help of a diesel mechanic mate.
I remember filling him the transfer case until oil started to come out of the fill plug hole so I am 99% sure it wasn't overfilled.

is it possible you got water in the transfer?

Been through any deep water/mud since you changed it?

Is it possible that the breather hose is disconnected somehow?

Just wondering if the fluid has been 'topped up' with water or mud?

That's a good point, bm0. My D40 had a transfer case seal replaced. Oil floats on water ... I saw this thread earlier and didn't join those dots.

I only joined the dots because it happened to me.....

if that is the case and you drain it.. its going to smell... worse than normal...

Old 45 series cruisers use to drain oil from g/box to transfer case or vice a versa, A seal between g/box and t/case use to bugger up

If it's overfull now but wasn't when filled then something is getting in. I can't answer about gearbox transfer seal, but perhaps the breathers are joined and allowing transfer of oil.

Check the level in the gearbox, see if it is high/low, then you will have a better start. I'd also be checking for water.

Thanks for replies guys.
I haven't been through any water at all or mud. The mrs did mention if water could have got in when I wash it down after a beach run which I do mostly. I tend to spray it all with water a fair bit when doing this and she tells me off for using to much water. I will check breathers and gearbox level over the weekend.

Cheers

PS The oil that came out was black and had no milky look to it like you would normally see if water was in the oil. If the water and oil separate when not in use this could mean like tony said and the water is on the bottom.

mgladwin said:

Thanks for replies guys.
I haven't been through any water at all or mud. The mrs did mention if water could have got in when I wash it down after a beach run which I do mostly. I tend to spray it all with water a fair bit when doing this and she tells me off for using to much water. I will check breathers and gearbox level over the weekend.

Cheers

PS The oil that came out was black and had no milky look to it like you would normally see if water was in the oil. If the water and oil separate when not in use this could mean like tony said and the water is on the bottom.

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just wondering what the issue ended being, i think i might have the same problem.

I also had a small oil leak from the Transfer Case. Took it to a mechanic and it turned out that one of the bolts had loosened and oil was seeping from there. Don't know how it became loose - however he nipped it up and problem fixed.