Transmission Draining Into Tranfer Case????

[Backcountry]

Hello all!

I posted a while back in regards to my transfer case being overfilled by about two quarts.

After a round trip of about 250 miles, I decided to have my tranfer case and transmission oil changed again just to be safe..

Because of my previous problem, I had the mobil service guy check the transfer case oil level. This time about half quart came out. I then had him check the transmissin level. Open fill plug to check level; could not reach oil with pinky, so a small piece of wire was used. The wire had to be inserted a ways to get any oil on it.
The transmission need about two quarts to fill it up. Now both are at proper levels.

My questions to you all are; Is it possible for the transmission oil to drail into the transfer case? And, being that I apparently drove with very low transmission oil; do you think I damaged anything??

The transmission and transfer case were both rebuilt about 5 months ago.

I felt no resistence, noise, vibration etc. that would indicate that there was a problem.

My vehicle is a 1973 Chevy 1/2 Ton 4x4. It has a 350 ci. Engine with a SM465 4 Speed Trans and NP 205 Transfer Case.

Any and all help would be greatly appreciated!

Thank you!

Guy

[79D604SPD]

If your transmission and transfer case are married(no small driveshaft connecting them) with an adapter, there is a seal on the t-case end(actually in the mounted in the transmission to transfer case adapter)that separates the gear oil between the transmission and the transfer case. The seal rides on the transfer case input shaft. If this seal is not in good shape, it will allow for gear oil mixing. If the seal is actually causing the problem, and the trans and t-case were just rebuilt, it makes me wonder why the seal went bad. Maybe check both trans and t-case vent hoses to see if they are plugged and not relieving excess pressure. This might have caused the seal to blow out. Or maybe the input shaft had some dirt on it, or it had a burr that damaged the seal. It is quite a job to remove everything(t-case, driveshafts) to check or replace the seal but I had a friend with a '74 K20 same problem and he had to replace the seal. Transfer case would have to be removed and the seal will be staring back at you in the end of the adapter. A nice transmission jack helps a lot.:grinz

[79D604SPD]

Really anytime the transfer case and the adapter and the transmission are split apart(like to replace a clutch), that seal should be replaced; but I don't know of anyone that does that. I think the transmission and t-case would probably be okay as long as you don't hear any noises or vibrations.
Jonathan