Topjimmyk

After a long day oh wheeling at the mounds in MI my tcase started to slip out of 4wheel. It did this a couple weeks ago when i went to silver lake but i put in in 2x4 and back into 4x4 and it stoped slipping. Well now it is making a lot of noises, its rattling a lot but it doesnt get worse with higher speeds it just makes rattlign and squicking noises. Ive been doing my research to see what the possiblilties could b but for now im goign to adjust the linkage b/c thats the easiest and cheapest fix to do first, but im afraid it could b my chain. My fluid was changed last winter and is full. I have a 98 sport with an np231. Any input would be nice i have never done any work on a transfer case before