Park it level, crawl under, the transfer case is shiny aluminum and it connects to the front drive shaft and you will see either two hex plugs or two big bolts facing the rear end. Get appropriate hex or socket, put drain pan under lower bolt/hex, remove bolt, allow to drain, remove upper bolt, once drained reinstall lower bolt, add ATF to upper bolt hole and fill till it runs out the top, reinstall top bolt/plug, done.