Okay, before you even start, I know that the Pittsburgh Steelers have not traded out of the first round since Dan Rooney put a stop to the practice of trading picks for players in the mid-60s. To be specific, 1967 was the last year in which the Steelers did not make a selection in the first round of a draft.
In my research, the Steelers traded their ninth-overall selection in the 1967 NFL Draft to the Packers in July of 1966 exchange for tight end Tony Jeter and defensive lineman Lloyd Voss, the latter of whom played six year for the Steelers.