After graduating from Harvard, Colbert clerked for the
New York City firm of Rathbone, Perry, Kelley, and Drye, which was the general counsel for the Chrysler Corporation. When Chrysler decided to hire an
in-house counsel in 1933, Colbert was chosen for the job. He was mentored by Chrysler head
K. T. Keller, who had Colbert learn about mechanics, engineering, and production, as well as handle labor negotiations and other legal duties. In 1935, Colbert was named vice president of the
Dodge division. In 1943, he was put in charge of the new
Dodge Chicago Plant and oversaw the construction of most of the
B-29 bomber aircraft engines used in
World War II. On December 27, 1945, he was promoted to president of Dodge. In 1949 he was made a vice president and director of the Chrysler Corporation. On November 3, 1950, it was announced that Keller was elected chairman of the board of directors and Colbert would succeed him as the company's president and chief executive. Colbert led the company during prosperous times fueled by the
post–World War II economic boom. However, by 1958, sales had dropped sharply, with only 165,059 vehicles being sold during the first quarter, and the company posted a loss. On April 28, 1960, Colbert was elected chairman of the board and was succeeded as president by
William C. Newberg. Colbert retained his position as the company's chief executive. Not long after Newberg took office, Colbert instructed the company's general counsel and independent auditors to look into Newberg's interests in vendor companies. On July 21, the board of directors announced that it had reached a settlement agreement with Newberg over $450,000 in profits he had made from his stake in two parts suppliers. A second company executive, Jack W. Minor, was forced to resign from his position as director of marketing for the
Plymouth–
DeSoto–
Valiant division after it was found he received $20,000 in sales commissions on Chrysler contracts from two transportation advertising companies he held ownership in. On January 27, 1961, Colbert disclosed that his wife had owned 444 shares in a Chrysler supplier. On July 27, 1961, Colbert announced he was resigning as chairman and president "for the good of the corporation". He was succeeded as chairman by
George H. Love and as president by
Lynn A. Townsend. Colbert remained with the company as chairman of
Chrysler Canada until his retirement on June 30, 1965. ==Later life==