transfer case fluid level over full

[rgoering]

1993 K1500 4wd truck with 241 C transfer case. I just overhauled the transfer case, refilled with tranny fluid to bottom of fill port. In a couple of days I noticed a small puddle of red fluid (I did find where the case had a slight leak), but the problem was when I pulled the fill plug to check the level, fluid gushed out. The case was way over full. Does th transfer case fill from the transmission? If so, is this right or is there a problem?

 

[Blue85]

Yes, the 4x4 transmissions are open at the back. There is a double seal on the input of the transfer case that is supposed to keep fluid separated between them. Was that replaced during the overhaul? Check the transmission fluid level, as it's likely low.

 

[rgoering]

Thank you, that makes sense.

 

[Wes Harden]

Make sure the transmission vent line is not plugged.
If vent is plugged even a new seal will fail.

 

[rgoering]

There is a vent line attached to the transfer case. I didn't notice where the other end goes. Does it go to the transmission and is that the line you are referring to?

 

[Blue85]

The transmission has it's own vent. Usually just a short tube up on the top where it's really hard to see from below. It may be possible to see it if you pull the T-case shifter. It may also be possible to lower the transmission / T-case a little with a jack so you can reach up there. I've never had a GMT400.

 

[Wes Harden]

Normally 4x4 have a hose on the trans vent, it will go up to friewall near hood on one corner.

If the trans has been out for any reason,it is probably not connected or even there.

The vent is on top of case near where the bell housing starts.
You can reach up and fell it with fingers.

 

[rgoering]

Thanks for the good tips.