Thomas Friedkin was the son of Jean and Kenny Friedkin. His father was a combat pilot and trainer with the British Royal Air Force during World War II. After the war, his father opened Friedkin Aeronautics, a flight school in San Diego, California, before founding Pacific Southwest Airlines in 1949 with a single leased DC-3. In 1958, it carried nearly 300,000 passengers. Friedkin learned to fly while he was a youth and in 1962, started working as a pilot for PSA.
In 1962, Friedkin's father died abruptly of a cerebral hemorrhage at age 47. In 1963, PSA went public and soon after, his mother also died, making the younger Friedkin the largest shareholder of the airline. Although he had a seat on the Board of Directors, he continued working as a full-time pilot for the carrier. The airline continued operating until 1988 reaching $500 million in revenues, when US Airways purchased the carrier for $400 million. Friedkin received just $3.4 million.
During the 1960s, one of Friedkin's hobbies was racing cars. He was friends with Carroll Shelby who had turned down an offer to become a distributor for Toyota Motors. Shelby introduced Friedkin to Toyota and Friedkin founded Gulf States Toyota Distributors (GST). Friedkin has built GST into a multibillion-dollar franchise that buys Toyota, Scion and Lexus cars wholesale and sells them—as well as parts and service—to about 150 dealerships in his franchise states of Arkansas, Louisiana, Mississippi, Oklahoma and Texas. GST's sales account for nearly 13% of Toyota sales in the United States. GST is a wholly owned subsidiary of the Friedkin Companies and ranked 53rd on the Forbes 2008 list of America's Largest Private Companies with revenues estimated at $5.7 billion.
GST's corporate headquarters is in west Houston with a 400,000-square-foot (37,000 m2) campus consisting of a five-story and a ten-story building, connected by a concourse and an eight floor parking garage. The complex includes a 40,000-square-foot (3,700 m2) training center, in addition to Gulf States Marketing and Gulf States Financial Services offices. Gulf States Toyota Distributors is one of only two remaining private Toyota distributors in the United States, the rest having been reacquired by Toyota. The other is Southeast Toyota Distributors, founded by the late billionaire Jim Moran.
By 2001, Tom Friedkin, then 66, had turned over responsibility for running the holding firm and its 3,000 employees to son Dan, but remained chairman and was content to dispense advice. "I'm kind of a bum these days," he told Forbes. "I am not a greedy person, and I don't have to make the last dollar there ever was."