The working title for the film was originally Shack Up on 101 but after lead Terry Moore allegedly complained, it was changed to Shack Out on 101.

The exterior scenes of the movie were shot on location in Malibu, California.

The opening credits give a special screen credit to "A Sunday Kind of Love" (written by Barbara Belle, Louis Prima, Anita Leonard and Stan Rhodes) but it is not heard as a vocal number or in its entirety in the actual film. The few scenes where music is used usually occurs in the shack bar where a jukebox is situated. Composer Paul Dunlap is credited with these selections.

A soundtrack album for Shack Out on 101 was also released (now out of print).

Lee Marvin and Keenan Wynn were lifelong best friends who first met in the early fifties and shared a love for motorcycle riding after Marvin developed a taste for it while filming The Wild One (1953) with Marlon Brando.

Shack Out on 101 was Marvin and Wynn's first film together but they would later appear together on numerous TV programs and reunite in 1967 on the big screen in Point Blank.

The original tagline for the film's poster was "Four men and a girl!"

by Jeff Stafford

SOURCES:
Lee Marvin: His Films and Career by Robert J. Lentz (McFarland & Co.)
Marvin: The Story of Lee Marvin by Donald Zec (St. Martin's Press)
Lee: A Romance by Pamela Marvin (Faber and Faber)
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