i have a02 ram 1500 5.9, the 4wd light is on. what shoud i look at first the truck drives and sounds fine

 

Welcome to the site. Try downloading the 02 Service Manual in the links in my sig and see if it helps. What issues are you having? What is is doing or not doing? When did it start? How long has it been doing this? What maintenance have you done on your transmission?