I was questioning about changing the fluids

the oil is given, but the front and rear difs, transmission, and transfer case my manual at 70000 says to change all if I tow anything or go off road. The local dealer said to wait till 100k . Would it be better if along with the oil I do the rear dig and transmission and wait on the others since I don’t really use the front dif and transfer only every now and then to keep it moving a little.
My 2015 Tundra CM 4x4 has just turned 70000 miles

 

Really up to you but I'd say the dealer wouldn't steer you wrong. Typically manufacturers call for trans drain/fill and filter every 60k ish but it wont hurt doing that and your rear diff at 70k and waiting for 100k for front diff and TC. Personally I am going to wait to 100k and do them all. No towing but I do use 4X4 weekly being in snowy mountain country. Nice SC tho, I like the matte silver grill center and bumper facade.