I own a Dodge 4x4. 1996 Model with a 360. All around it's a great truck with about 120,000 miles on the clock. Here in Indiana the 4wd gets used about 3 or 4 times a year. One of the few times my wife drove it this year was when we had a little snow. She complained that the 4wd was making a squeaking noise. It's beena long time since it has had the transfer case serviced. I drove it and sure enough it was pretty gnarly sounding. It was barely noticable at low speeds but the faster I went the more noticeable it was. My friend and I had a look because I hoped it was just a CV joint. They were solid but when I twisted the shaft in my hand I could hear a nasty clunk from the transfer case. I was also unable to loosen the drain plug to check the fluid level. It's a big ass bolt and on there super tight.Ill keep trying but until I can get in there any ideas as to what it could be. I'm not going to fix it yet as winter is winding down and I don't use it much to begin with. It also is very quiet for the first five or ten minutes so I could use it in short bursts if I had to. I know it's not much to go on but if  this sounds familiar to any Dodge owners let's hear it. I'm going to keep this truck till it shits it's guts out on the road but would rather it be later than sooner.