Honestly I've never heard of transmission oil cooler as a maintainance item.
My motto is, If it ain't broke don't fix it.

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"What you hear in a great jazz band is the sound of democracy. “The jazz band works best when participation is shaped by intelligent communication.”
Harmony happens whenever different parts get to form a whole by means of congruity, concord, symetry, consistency, conformity, correspondence, agreement, accord, unity, consonance…….