Gade was born in Perivale in the United Kingdom, the daughter of Indian immigrants, and is one of three sisters. The family spent three years in India between her ages of nine and twelve, a period during which she and her younger sister Teena developed an interest in engineering. On returning to England, both sisters became devoted followers of Formula One, drawn not by glamour but by their fascination with what the machines could do — a self-described obsession. Her sister Teena also went on to become a race engineer.
Gade studied at the University of Manchester, graduating in 1998 with a Master of Science degree in aerospace engineering. She entered as one of only five women in a class of approximately 100.
After graduating, Gade spent six and a half years as a vehicle refinement engineer at Jaguar Cars. Alongside her full-time engineering role she worked part-time on racing teams in the Formula BMW, A1 Grand Prix, and GT racing categories. Her first experience at the 24 Hours of Le Mans came in 2006 as part of the Chamberlain Synergy Le Mans Prototype team.
In 2007, Gade joined Audi Sport Team Joest, the factory operation at the heart of Audi's long-running LMP1 programme at Le Mans.
Gade's defining achievement came in 2011 when she led the engineering of the car driven by André Lotterer, Benoît Tréluyer, and Marcel Fässler to overall victory at the 24 Hours of Le Mans — becoming the first woman ever to hold the role of lead race engineer on a Le Mans-winning car. The team repeated the achievement in 2012 and again in 2014, giving Gade three Le Mans victories in total.
In December 2012, she was named the FIA World Endurance Championship's Man of the Year award — the first woman to receive the honour — recognising her contribution to Audi's dominant season. That same month she received the C&R Racing Women in Technology Award. In 2013, she was appointed an ambassador for the FIA Commission for Women in Motorsport, and served as a Formula Student ambassador in both 2013 and 2014.
From 2012, Gade also worked in Germany contributing to new race car development for Audi alongside her race engineering duties. When Audi closed its LMP1 programme in 2016, she departed the team.
Following Audi's LMP1 exit, Gade joined Bentley Motorsport. In 2018, she moved to IndyCar, taking on the role of race engineer for James Hinchcliffe at Schmidt Peterson Motorsports on the No. 5 car. The programme ended abruptly when Hinchcliffe failed to qualify for the 2018 Indianapolis 500.
In 2019, Gade was hired by Canadian engineering company Multimatic to engineer the No. 77 Mazda RT24-P Daytona Prototype International entry in the IMSA WeatherTech Sportscar Championship. Later that year she was appointed president of the FIA GT Commission, overseeing global grand tourer racing at the governing body level.
Gade's three Le Mans victories place her among the most successful race engineers in the history of the event, and her 2011 win shattered a barrier that had stood since the race's founding. Working at the top level of endurance motorsport in a role that remains male-dominated, she demonstrated that engineering excellence — not gender — determines outcomes at the highest level. Her advocacy work through the FIA Commission for Women in Motorsport and her role as a Formula Student ambassador have extended her influence well beyond the pit wall.