I have had leak from front seal in my NP249. When i got the car i couldnt feel any oil in there with my finger tip. Someone said i should use normal ATF +4 or whatever i got, so i started to use ATF +4 and i had to add now and then. After i changed oil on my tranny (AW4) i started to use the same oil in my 249 (DexIII). Now its not leaking anymore. i have new seal, but i didnt mange to remove the nut, i now have the tools to do it, but since its not leaking anymore, should i still replace it? Could changing to DexIII in the 249 actually stop the leak??

 

Unsure about the leak issue.
However. The AW4 automatic transmission takes Dex/Merc III ONLY!
If you use ATF 4, problems may arise that cannot be easily fixed.
On your 249 transfer case, it has a 'viscous coupler'. People use ATF 4 and Dex/Merc III. However I would stick with Dex/Merc III for your 1993.
Check your owners manual to be certain.
Chrysler supplies ATF 4 but does not have Dex/Merc. So they obviously want to sell ATF4.
The AW4 is made by Asin Warner. They say use Dex/Merc III only.

 

i know that i need to use DexIII in the AW4. When i replaced my oil in my AW4 i started to use the same oil in the 249 and then the leak stopped.

 

Obviously the Dex softened the seals in the case so it stopped leaking. I'd stay with the Dex until the leak started again, at which time, I'd replace the seal.