The 2003 Tropicana 400 was the stock car race of the 2003 NASCAR Winston Cup Series season and the third iteration of the event. The race was held on Sunday, July 13, 2003, in Joliet, Illinois, at Chicagoland Speedway, a 1.5 miles (2.41 km) tri-oval speedway. The race took the scheduled 267 laps to complete. At race's end, Penske Racing South driver Ryan Newman would stretch out his fuel mileage well enough to coast to the line and win his fourth career NASCAR Winston Cup Series win and his third of the season. To fill out the podium, Tony Stewart of Joe Gibbs Racing and Jimmie Johnson of Hendrick Motorsports would finish second and third, respectively.

The Camping World 400 was a NASCAR Cup Series stock car race held annually at Chicagoland Speedway in Joliet, Illinois, from 2001 to 2019. Previously, the race was held in July from 2001 through 2010, with night races held from 2008 to 2010. From 2011 to 2017, the races were held as the first race of the Cup Series playoffs in the round of 16. In 2018, as part of the schedule realignment, the race was held on the last weekend of June.