Eaton was born the youngest son of John David Eaton and Signy Eaton. His family provided the financial resources that enabled him to acquire competitive machinery at a time when North American access to top-level European racing required both connections and capital. He was described by the motorsport historian Mattijs Diepraam as a typical Northern American single-seater racer — well-bred, well-funded, and versatile. After retiring from racing he later served as president of Eaton's department stores during the company's final decade, overseeing its decline from Canada's dominant retail chain to ultimate liquidation.
Eaton entered the Canadian-American Challenge Cup in 1967, acquiring a McLaren M1C and achieving a third-place finish at a wet Laguna Seca as his best result of that year. In 1968 he upgraded to a McLaren M12 for Can-Am and an M10 for North American Formula A, developing into a genuine front-runner in both championships. He was the top Canadian finisher in the Can-Am Series in 1969 and remained in the series through 1970, when he also drove BRM's P154. The P154's handling was described as terrifying by those who drove it, with several structural failures and unreliable engines preventing any race finishes. He participated in the Canadian Formula A series in 1969 and the Continental Series in 1969 and 1971. An attempt to qualify for the 1970 NASCAR Grand National Series event at Charlotte Motor Speedway was unsuccessful.
Eaton's Formula One career was conducted entirely with British Racing Motors. He made a guest appearance in the BRM P138 at the 1969 United States Grand Prix at Watkins Glen — his F1 debut on 5 October 1969 — qualifying last and retiring. He repeated the same outcome at the 1969 Mexican Grand Prix. His home race that year, the Canadian Grand Prix, was given to Bill Brack for the occasion.
Impressed enough by his conduct, team manager Lou Stanley offered Eaton a full-season contract for 1970, as a third entry alongside Pedro Rodriguez and Jackie Oliver. The season ran under the Yardley sponsorship livery from Spain onward. While Rodriguez developed the new P153 into a front-runner and took a victory, Eaton's best qualifying position was eighth at Mosport and his best race result was tenth at the Canadian Grand Prix. He failed to qualify at Monaco and Jarama. His highest classified finish across the entire 1970 season was 12th at the French Grand Prix.
For 1971 Eaton was returned to guest status, racing the BRM P160 at the Canadian Grand Prix at Mosport Park and finishing 15th. It was his final Formula One appearance. He scored no championship points across 13 World Championship entries and 11 starts.
The broader context of the 1971 Canadian Grand Prix was notable: BRM fielded four drivers that weekend — Siffert, Ganley, Marko, and Eaton — a preview of the unwieldy multi-car setup Lou Stanley would expand further in 1972.
After his final Formula One drive, Eaton competed in sportscar events for Ferrari, entering at Sebring, Le Mans, and Watkins Glen, though results remained elusive. He retired from all racing following the 1972 Daytona 6-hour race.
Eaton was the only Canadian driver among the small group active in the late 1960s — which included Al Pease, Eppie Wietzes, Tom Jones, Bill Brack, John Cordts, and John Cannon — to hold a full-time Formula One seat. Gilles Villeneuve, who would transform Canadian Grand Prix racing, emerged several years after Eaton's retirement. Eaton was inducted into the Canadian Motorsport Hall of Fame in 1994 and received an honorary doctor of laws degree from St Francis Xavier University at a special convocation in April 1996.