th400 pressure?

[Detroit Dan]

when I had the trans back to change the flexplate, I happened to check the transfer case fluid and found it was overfull, right to the top and had been coming out the vent also. I crackedthem apart and replaced the seal between them, which had obviously failed. I didn't know whether the fluid pumped into the t-case because the seal failed, or if the seal failed because trans pressure had gotten too high. So I take it for a drive today, really only the second time I've driven it so I was nervous. After about 4 miles it apparently burped fluid up out of the dipstick tube, slobbering a little on the exhaust which burned off rapidly but in an alarming manner.

What could be wrong? It has been flushed out and filter changed. Could the vacuum modulator do this if it went bad or a vacuum line failed? A clogged tranny cooler line maybe? Hope somebody has the answer, I need to drive it again, and this time a few miles farther than todays trial run.

Oh yeah, it's an 82 K30 454/th400/np205

 

[6.2 turbo]

Maybe the dip stick is giving you a false reading/wrong stick and you overfilled it.

 

[Detroit Dan]

well the trans and t-case are pretty dirty, there is a lot of crud in that area because the t-case vent was working and spewing the overfill coming out of the trans. So all the dust and dirt stuck in it and caked on. The truck was mostly driven on dirt roads, so it is mostly spotless except where there was some leakage, and that's all caked-on crud. So I got my fingertips on the vent hose and all I could do was snap it against the bellhousing a few times, hopefully enough to free up any junk in it.
Trans turned out to not be overfull. Lot of places I found online said the th400 will spit out any fluid that you overfill. I ended up getting it warmed up and finding nothing on the stick, had to put 4 1/2 quarts in it. Here's what I think happened: when we changed the seal after the tranny pumped it's fluid into the t-case, I didn't realize it had pumped out the torque converter too. So I filled the pan up with 7 qts, but after running it and moving it around a little it got drawn into the converter, leaving the pan low. I don't know if a low condition could cause pressure, or a plugged vent is still at fault, but I rattled the vent and topped pan off and it is working, Also possible the dipstick wasn't seated in the tube. Drove it a few miles with no problems, no burping, spewing smoke or slipping,

I checked the t-case, it was not overfull so it seems like the seal stayed intact. In fact, there was nothing in it. Apparently after we put it back up some nitwit forgot to refill it. It's not leaking. Really lucky I didn't drive it much, and this spurt actually saved me by making me look into it. It was last winter when I worked on it last, so it sat for many months and I'd forgetten what else we had left undone I guess. With a half empty tranny and an empty t-case, I would have done some serious damage once I put it on the road. But all I did was move it to the new house, it will probably sit there for the winter.

Once again my poor memory and attention span almost bit me. Oh well, I guess I'd rather be lucky than good!

Thanks for the help.
__________________