72 GMC K2500 TH350 w/NP205 dilemma

[kmoore]

HELP!!

Looking for some insight from you experts with knowledge of what was original in my 72 K2500 GMC Sub. This is out of my league, know enough about an automatic transmission to be.......well in the position I am in now!

Problem started with a leak that was spraying fluid all over the exhaust while I was driving and smoking pretty bad, looked under the truck (after cleaning everything up to find the source) and drove it again with the same problem. The only place that it was obviously coming from was the transfer case, well that did not seem right.....that would be gear oil....right? Tightened everything up that I could on the transmission and transfer case again and still seemed to be coming from the transfer case. I had Transmission issues anyway so time to spend some money on the Burb since it has been a while right? Towed it to an AAMACO dealer who stated that they had experience with 40 year old transmissions and this would be a piece of cake.

Fast forward to now: There should be a seal between the transmission and the transfer case but there is none. I do have fluid in my transfer case but they have never seen that before nor his sources/advisors. "They can put it all together and should be all right"

If there was not a seal it has been that way during the many miles I have driven it with no issues before. He said everyone stated (his transmission sources) that it should have been a TH 400 since it is 4 wheel drive and 3/4 ton. I am not the original owner but my build sheet and all paper work shows TH transmission with an * but no other denotation of what the* means or 350 or 400 listed.

The question is should this have been a TH400 or did they put TH350 in 3/4 four wheel drive units? All mounting holes/brackets and geometry match to what is in there now and no sign of any changes.

What about the seal issue and tranny fluid in the transfer case? May have made a poor decision in AAMOCO but I thought I was doing good with national brand and resources.

If there was an seal/plate available that would change all the spacing of the mounts and would then lend one to think it was not originally set up that way....unless the TH400 was a tad bit shorter. Now I am confused.

First 3 pics are my transfer case/TH 350, and following 2 are from his source of a TH400/TC with a seal or plate.

I do appreciate any help or insight that anyone may have.