your transfer case just uses gear oil, same as what you put in the diffs. not transmission oil, that is different.

you don't have to remove transmission to get at detection switches, but you would probably have to remove the t-case itself b/c they are mounted on top of the case. if you have a body lift or 2 inches or more, you can squeeze your hands up there and get at the switches, but with stock body mounting, it is very difficult if not impossible to get at them without taking the case down.

97 Montero SR w/Mitsu Adj Shocks & Rear Diff Lock ARB Front Diff Lock 4.9 Ring/Pinion 3.15 transfer box 43:1 crawl ratio 2" suspen lift 2" body lift 2" Gas Tank Lift 35x12.5 MTRs 15x10 Wheels Rock Sliderz ARB front bumper w/12k winch Custom rear bumper