Lots of stuff has been said But this came out of a gm master tech with 35 years in the field
Specs say 50k flush and 100k filter/flush
he says 25k flush 5ok filter/flush
He also has 5 gm cars all with over 250000 miles and hasnt lost a tranny yet since heat and contaminants are the killers
also depends how you drive under extreme driving he says the intervals should be shorter
Im incline to trust the guy considering trans is his specialty and he has just about every gm and ase cert you can have