With teammate Ryan Briscoe, the two-time Indianapolis 500 winner and Dancing with the Stars champion shared the driver's seat for the 10-hour spectacle.
Briscoe started early in the day, and Castroneves completed the race.
"This was a terrific win for Helio and Penske Racing tonight in the 1,000-mile Petit Le Mans race," Bed Denker, senior vice president of the Penske Corp., told PEOPLE. "Helio is elated and proud of his team after what has been a long week for him."
Passport SurrenderedCastroneves, 33, was indicted Thursday for not paying U.S. taxes on more than $5 million in income. His bond was set at $10 million. Of that, $8 million is security from one of the Brazilian racer's personal accounts in the Netherlands.
"He surrendered his passport and has permission to travel anywhere in the U.S. for business," his lawyer, Mark Seiden, told PEOPLE on Friday. "For travel overseas, including an upcoming race in Australia, he needs to get permission from the court."
Seiden believes Castroneves is a superb and accomplished professional racecar driver who took bad advice.
"He is not a tax lawyer and not an accountant," says Seiden. "He relied in good faith on competent professionals for tax advice. We don't feel he did anything wrong, and will be vindicated in court."
If convicted of all charges, Castroneves faces a maximum of 35 years in prison.