My 97 Dakota 2wd 5.2 RE44 with a good cooler and always use ATF-4 got 287000 miles out of the factory tranny. Changed fluid and filter around ever 30K. Even then the clutches and bands were not toast at the tear down.
I of course never raced it but did tow with it. Towed several B bodies but never up any of our long 7% grades here.