Starting as a driver at MGM after a stint in the Army, Brubaker worked his way up to head of transportation at the studio. He then moved over to production, where he developed expertise in all phases of filmmaking. He was production manager on Raging Bull, Comes A Horseman, and New York, New York; associate producer on Rhinestone, Rocky III and True Confessions; line producer on Patty Hearst; and co-producer on Rambo III. His producer credits include most of Sylvester Stallone’s films in the 1980’s—Over The Top, Cobra, and Rocky IV. One of his favorites is a film he executive produced, The Right Stuff.

During his career, and between films, Brubaker has often served as a mentor and advisor to young people. He has been a lecturer and teacher at the Film and Television Department and Extension Program at UCLA; served as an advisor to student filmmakers at USC; and served on the board of Street Lights, which trains disadvantaged young people in film crafts. He creates opportunities for these trainees on his films providing them with the experience necessary to forge a career in the business.

Brubaker has also been a member of the Los Angeles Film Commission Task Force (1994-1995). He is a member of Directors Guild of America, the Academy of Motion Picture Arts & Sciences and the Teamsters Union.