Transmission oil keeps blowing out of vent tube

Same thing happened to mine last summer. Follow the vent tube down to the transfer case and there will be a check valve with three tubes going into it. This check valve is defective. Unfortunately you need to drop the transfer case out in order to fix it. I had to replace the check valve and the gasket between the tranny and transfer case. Good luck

Thanks for the info.

had transmission line come off while driving put line back on put 4 and a half quarts in show on stick but driving1 mile dose not show on stick should i change the transmission filled ty

I had to same problem. I'm not trying to spend a lot of money on an old vehicle so what I did was take a 3/8 copper tube and bet it into a U. Then I connected one side to the overflow tube and put the other end in the fill tube. Works great, no more leak. The only question I have is if the check is malfunctioning will it affect the trans at some point. So far so good.