Known for his numerous appearances on the television series The Rockford Files, he is best remembered as the older brother of the show's star, James Garner. He also appeared in several 1970s, '80s, and '90s films, including Wild Rovers, Sunset, and Maverick.
Before beginning his acting career, he attended Norman High School in Oklahoma, where he led his school's championship-winning basketball and football teams. He went on to pitch for over a decade for a Pittsburgh-based minor league baseball team.
An avid golfer, he taught his My Fellow Americans co-star Dan Aykroyd to handle a golf club during a scene in that film.
He was born Jack Edward Bumgarner in Norman, Oklahoma, and he grew up in a family of three boys (Charles, Jack, and James). His marriage to Betty Bumgarner resulted in a daughter named Liz.
He and his famous brother, James Garner, changed their surname from Bumgarner to Garner upon moving to Los Angeles to pursue screen acting careers.