liftedstepside

Looking for some opinions or even some factual info on missed maintenance intervals for the driveline. My '16 Sierra has 92k on it and I remembered there were some notable services due at 90K, specifically the trans and t-case. These were also due at 45k but were not done. I've had zero issues with either component, same goes for my father with his '14 Sierra and he hasn't touched either with 150k on his truck. Wondering what I should do, Keep going with the old wives tale of "if you haven't changed it yet, DONT" ? Or just get it done... Thanks!