I have bet a lot of people on these forums aren’t even technicians..... it’s a fact that replacing oil not only keeps the oil from loosing its additives by wearing them down but also removes dirt and moisture that is absorbed by the fluid.... I’m a master diesel tech and Allison and all other major manufacturers recommends routine maintenance hence why repairs are covered if it was maintained and not covered if it had lack of maintenance I have yet to have one transmission to blow due to maintaining ans I like to change ever 40- 45 thousand miles