John D. (Jack) Dunning, 74, a 40-year MGM editor and postproduction exec who won an Oscar for editing William Wyler’s 1959 “Ben-Hur” with Ralph E. Winters, died Feb. 25 in Santa Monica, Calif., of a heart attack while under treatment for cancer.

Dunning also received an Oscar nomination for editing William Wellman’s 1949 World War II pic “Battleground.” His other credits included “Show Boat,” “Julius Caesar,” “Raintree County” and “Cimarron.”

When he retired in 1978 from MGM – his only employer during his long film career – Dunning was v.p. in charge of all pics and tv postproduction for the company.

A Los Angeles native, Dunning started with a night job as an apprentice film editor for MGM in 1935 while he was still attending U. of California at Los Angeles, from which he graduated in 1939.

By the time he retired from MGM, he had worked under eight studio chiefs, from Louis B. Mayer through Richard Shepherd. Along with longtime Metro senior editor Margaret Booth, he was a major contributor to the postproduction look for which MGM pics were known in those years.

Dunning’s only time away from MGM came during World War II, when he worked on films in the U.S. Army Signal Corps from 1942 to 1945. That stint included work as an assistant editor with Frank Capra’s propaganda films unit.

During his career at MGM, Dunning also edited such films as “Cass Timberlane,” “Homecoming,” “Julia Misbehaves,” “The Next Voice You Hear,” “Across The Wide Missouri,” “The Wild North,” “Rhapsody,” “The Last Time I Saw Paris,” “The Tender Trap,” “The Brothers Karamazov” and “The Swan.”

He remained a staff editor until his promotion in 1960 to editorial supervisor. In 1969 he was made head of the editorial department, and in 1970 he was named executive postproduction manager.

Dunning was given his final postproduction v.p. stripes in November 1977, eight months before his retirement.

Survived by a daughter, Barbara Dunning, an assistant film editor; two sons, John and Robert; a sister; and three grandchildren.

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