You're probably right that there's a little leeway on the type of fluid (ultimately). #2, a lot of small town family dealers will sell fluid right out of their bulk barrels ...if you bring in your own container/s. I know two around here which do (plus a GM dealer too) ...and the cost is considerably less. That's what I do. You have to contact the parts dept. Call a couple small dealers. Larger dealers will just laugh at the idea.
#3, I have a great transfer case story ...I'll try to be brief (some of you might have read this): Years ago we planned an "out-west" family vacation. Just going from the WI area to the Black Hills Area (incl Devil's Tower WY) and back. A trip we've done several times over the yrs. 1995 Jeep Grand Cherokee with Select-Trac transfer case. What is that ...a 232? It's a distant decendent of what's in the Rams. That's about a 2000-2200 mile R/T Journey (~3200km) including all the side trips. Before leaving I checked & topped off all fluids *except* the xfer case ...because it started to rain and vehicle was outside and I didn't want to lay on my back in the rain (hint -- I should have!). I vowed to throw the big wrench in and check it at the hotel the next morning. Anyway, with smiles on our faces we headed out to our journey.
Well to move the story along, we had a great time on the family/kids vacation, weather was mostly great, and, although a nagging voice in the back of my head kept telling me to check the fluid every day, something always came up and I didn't. Even though I knew I should have. When I got home ...guess what the first thing I did was? I pulled the upper plug and stuck in a piece of wire. Nothing. Then I flipped the wire and put the long end in -- Nothing. Hmm... strange. Pulled the bottom plug ......and literally no more than 3 teaspoons of fluid trickled (and I do MEAN trickled) out into the pan. It made a pool of fluid about 5-6" in diameter (~15cm)!
Now you'd think it would be toast! I just drove a thousand miles only making bathroom/food breaks to get home with virtually NO fluid in it! LOL. It wasn't super hot. The output bearings weren't excessively sloppy. Being it was Sunday and my wife needed it for getting to work in the AM, I put Dextron II (suggested fluid) in it and crossed my fingers. Oh, and I forgot to mention, the Jeep Grand Cherokee already had about 230k mi on the odometer (368k Km). I changed the fluid again after a week.
End of the story is, she drove the vehicle several more years w/o problems or noises. At about 300k mi (480k KM) , the pinion bearing needed to be changed. At that time ..out of curiosity I pulled the transfer case off the tranny and pull it apart. I've rebuilt several transfer cases over the years, I expected to see blue shafts, chipped teeth, a stretched chain and probably a bunch of shavings. I saw NONE of that! Nothing was blue or chipped -- it looked like freekin new inside. I'm not joking. Other than the usual fuzz of iron dust on the magnet. The output shaft bearings were still relatively tight. There was literally no reason to do anything to it ...so I put it back together. She ran the vehicle until about 335k mi (536k Km) ...and at that point rust was getting the better part and we bought a newer Jeep.
Yeah I was amazed. If that's not a torture test, IDK what is. The oil pickup tube is at the very bottom of xfer case ...and that's probably what kept it from seizing up (??).
Sorry for the long story...
