Molinaro portrayed Big Al Delvecchio, the owner of Arnold's drive-in, in the classic TV series. He also appeared in the "Happy Days" spinoff "Joani Loves Chachi."
His son, Michael, confirmed the actor's death to TMZ and said that Molinaro suffered from bad gall stones.
See more of Molinaro on the iconic show:
Younger audiences may recognize Molinaro as Al from Weezer's "Buddy Holly" music video, which was set in the "Happy Days" drive-in and featured edited footage of Fonzie (Henry Winkler) dancing with girls.
Born in Kenosha, Wisconsin, Molinaro also appeared in "The Odd Couple," "Punky Brewster" and "Step by Step."
He is survived by his wife, Betty and his son Michael.
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