Thank all of you for trying.I spoke to several older guys who gave me a way to contact folks who mostly provided me with enough info to make me dangerous!1984 they had 2 diff.systems called "Command trac" which was a part time shift on the fly and "Selsct-trac"which allowed the option of fulltime 4x4.Most agree that during all of the advertising flury,there was an option called "Quadratrac"which gave you limited slip in both axels and all have this displayed on either the fender or quarterpanels.I did have an old 69 J-10 with this setup.It would go up a tree because of the real 4 wheel drive.It had the old 360" AMC v8(not tobe confused with Mopar 360's)and was powerful but,was geared so low that it drank fuel like mad.Tough??It had a full size tree fall onto the roof,when the previous owner miscalculated.It din't even bust the windshield alto it hammered the roof into a twisted mess.They used a jack to gain entry,the roof never leaked and the dorrs shut perfectly.I only gave it up because the frame was rotten badly and I tripled my$ by selling it.If anyone needs the info about trans used in which jeeps for the years from 1945-71 was an T-90,prior war years used an Y-84 and after that,I got a huge list if ya need to know,go to
www.jeeptech.com/trans/ and all are there.