I've used DexIII for over 350,000 miles in my 95 1500. Not bragging,just a fact.

 

ATF+4 Synthetic. your tcase and tranny will thank you!!!! vavoline makes it!! and well worth the price i think.. its in all my mopar vehicles.. and vavoline is the only brand i use.. but its a pain to find sometimes.. instock atleast

 

could you also use royal purple tranny fluid?