McCloskey's wife, Leslie, told the Detroit Free Press' Perry A. Farrell in May that McCloskey was suffering from Alzheimer's disease.
McCloskey was one of the architects of the "Bad Boys" era for the Pistons that saw the franchise win NBA titles in 1989 and 1990.
Prior to McCloskey's arrival, the Pistons had been a somewhat consistent presence in the playoffs but hadn't reached the NBA Finals since 1956, but between 1979 and 1981, Detroit had won 37 games. In short, McCloskey inherited a total rebuilding job.
By the time he left, the franchise was transformed. In addition to its two titles, Detroit lost to the Los Angeles Lakers in seven games in the 1988 NBA Finals and fell to the Michael Jordan-led Chicago Bulls in the 1991 Eastern Conference Finals.
The legacy of the Bad Boys has far outlasted McCloskey's tenure and the careers of the key stars.
And McCloskey played a key role in making in happen.
In addition to drafting Isiah Thomas, Joe Dumars, John Salley and Dennis Rodman, he earned the nickname "Trader Jack" for his wheeling and dealing behind the scenes. Vinnie Johnson, Bill Laimbeer and Mark Aguirre were among those McCloskey acquired through trades.
While he has yet to receive enshrinement in the Basketball Hall of Fame, McCloskey arguably had as big of an impact as any NBA front-office executive in the 1980s.