Tom started competing at a very early age, which was natural being the son of an ex-driver, mechanic and team manager Gerard Dillmann. He has taken his experience by competing in the most recognized formula series in Europe to climb up the ladder.
Tom is a race winner or at least a podium finisher in all the categories he raced which includes Formula Renault 1.6, Formula Renault 2.0, Formula 3, GP3 Series and GP2 Series the Formula 1 feeder.
In 2004 at the age of 15, after three succesful seasons racing go-karts, Tom entered the Belgian Formula Renault 1.6. In a family team run by his father, he finished 5th in the championship with a victory in Spa. After a few races in Eurocup Formula Renault 2.0 in 2005, he signed for a complete season at the age of 17 with SG Formula. He took his first podium in Misano but lost three in the next races after he had to retire for a recurrent eletronic failure. Tom finished the year strongly, he won his first race in Le Mans in the French championship, took an other victory from pole in Magny-Cours and two second places in the Eurocup final in Barcelona behind the champion. It was just on the grid of the last race that Helmut Marko came on the front row to invite Tom to a Redbull shoot-out in Estoril.
Tom entered the high level Formula 3 Euroseries with ASM and the financial support of the Redbull Junior Team in 2007. He was the youngest driver on the grid and his team-mates were Romain Grosjean, Nico Hülkenberg and Kamui Kobayashi. He impressed in the pre-season by being the quickest of the team but a crash in Nogaro had big consequences. He suffered a broken sternum and vertebra that took him away from the track during two months. Nonetheless, dispite missing the first meeting, he finished 9th in the championship after securing three podiums in his rookie season.
In 2008 Redbull decided to place Tom in his former team in Formula Renault but newcomer in Formula 3, SG Formula. After three unsuccessful meetings, he was fired of the program for not having found the part of budget asked by RedBull.
It marked the beginning of a very tough time for Tom without any sponsors. He raced again with Swiss team Jo Zeller racing two months later on the Nürburgring. This come back in Formula 3 Euroseries was a great revenge as he took a podium and a fifth place beating all the RedBull drivers. From mid-2008 Tom answered the calls from Formula 3 teams in need of results and feed back. In the F3 Euroseries for HBR Motorsport and Motopark or in Italian F3 for Europa Corse, Ghinzani, Victoria and Eurointernational.
However it is in the German Formula 3 that Tom gave a new boost to his career. After he impressed at the end of 2009 by securing three wins and three poles in six starts for Neuhauser Racing, HS Technik aiming at the title, offered Tom a seat for the entire 2010 season. It was the first time in three years that Tom could compete in a full season and he brilliantly took the title with six wins and seven poles beating Daniel Abt and Kevin Magnussen.
At the end ot the season Tom tested for the first time a Formula Renault 3.5 in Alcaniz. As a reward for his title in the German Formula 3, he was invited by Renault sport, with all the Formula 3 and Formula Renault champions around the world. Tom did the fastest time of the session beating illustrious young drivers.
It is after this succesful season that Tom found the management and financial support of Luxury Racing to make his debut in the GP3 Series with Carlin. The season started with a pole position and a podium in Istanbul. Despite being third in the championship after the first meeting, Tom had to miss the next race due to a financial disagreement with his team. He made his return for the third round with Addax for the remainder of the season. Tom showed good speed in GP3, especially in qualifying where he had the third best average. Technical problems and two wrong choices of tires during mixed conditions costed him many points.
Well known for his speed and feedback Tom was also the test driver for Volkswagen Motorsport in Formula 3 during the 2010 and 2011 seasons. He also raced in Spielberg for Motopark in the F3 Euroseries and was the best Volkswagen driver of the meeting with a fourth and third place in the two main races.
To finish the 2011 season Tom did his first GP2 test with iSport in Jerez. After he impressed the team, Tom did the second test in Barcelona and posted the fastest time, half a second clear of the field! Following those two test days, Tom gained the opportunity to race in Abu Dhabi for the GP2 Final. Against many experienced driver and for his first time on this track Tom impressed by finishing sixth in his first ever GP2 race and did even better the next day by taking his first podium!
Following his promising debut in GP2, Tom had offers by the best teams. The lack of budget prevented him from signing with one of them and he even had to attend the official test in Jerez without knowing if he was going to drive. The Ocean team gave Tom a seat for two days and the Rapax for the last day, something extremely rare. He was the best rookie. He was then invited to test the last two days in Barcelona by Rapax. Despite missing the first day Tom finished 10th, 5th, 3rd and 1st of the 4 sessions. Those results impressed many people in the paddock but Tom was only confirmed at the last minute for the first race of the season in Malaysia. He continued race by race as the savior of a struggling Rapax team.. He took his first victory in GP2 in Bahrain after only three meetings! Tom could not race the entire season because of a lack of budget. Nevertheless he could achieve great results when given the opportunity, entering the very closed circle of GP2 race winners the most competitive category before Formula 1 in his rookie and partial season. Everyone in the paddock and even some important Formula 1 persons agree that Tom has the talent and deserves a real opportunity at this level.