When Lightning McQueen, The King and Chick Hicks finished the previous Piston Cup race in a three-way tie, the organizers choose that all three racers must compete in one last race at the Los Angeles International Speedway in order to determine who will win the Piston Cup. Chick is the first to arrive at the track, while McQueen is reported missing during Mack's journey to Los Angeles. During McQueen's search, Chick spends practice time around the speedway, while also gaining many fans including McQueen's own fans Mia and Tia. Five days later, the press find McQueen in Radiator Springs, and immediately take him to Los Angeles in time for the race the next day.
As the race starts, McQueen gets a poor start, as a result of him daydreaming about his new friends from Radiator Springs. After daydreaming once again and spinning onto the infield, McQueen becomes lapped by The King and Chick, but gains his confidence after seeing that his friends have come to assist him as part of his pit crew. With an easy pass to unlap himself, McQueen spends most of the laps on catching up to the two other racers, and despite Chick's dirty moves, McQueen eventually takes the lead after using a trick he learnt from Doc Hudson to prevent himself from spinning around on the infield. Moments later, Chick, tired of The King's defensing, rams him off the track, resulting in The King having a huge crash. However, McQueen, upon seeing the crash, stops before the finish line and pushes The King across, while Chick wins the race. While Chick wins the Piston Cup, the fans give the attention to McQueen for his good sportsmanship.
The last race in the 2016 Piston Cup season is held at Los Angeles International Speedway. By then, Lightning is one of very few veteran racers still competing as most of them have been replaced by next-generation racers. Before the race, he witnesses fellow racer Brick Yardley trying to convince his sponsor not to fire him and finds out that Bobby Swift has also been replaced.
Lightning performs well throughout the race, though he is unable to pass Jackson Storm. On one lap, the two head into the pits for a tire change. Lightning leaves the pits first and takes the lead, but it is not long until Storm catches up and reclaims it. Desperate not to lose, Lightning pushes himself in an attempt to catch up, but only results in crashing.
- The track takes inspiration from the Auto Club Speedway.
- It is a mix of the Los Angeles Memorial Coliseum, the Arroyo Seco in Pasadena (also the location of the Rose Bowl), and the Auto Club Speedway in Fontana.
- The scoring pylon takes some resemblance to the one at the Indianapolis Motor Speedway, as does the one at the Motor Speedway of the South.
- In the film, Darrell mentions the final race having an attendance of nearly 200,000 cars, but in production terms, there were really only 100,000 plus 1,500 in the infields and aisles and 13,000 entering the stadium to find seats. This is nearly twice as many as the 60,700 cars in Motor Speedway.
- In the race Cars 3, it is implied that Lightning is the sole veteran racer still competing. Some book adaptations of the film even state it directly. However, there are actually ten other veterans in this race: Reb Meeker, Buck Bearingly, Brian Spark, Rev-N-Go Racer, Ralph Carlow, Dino Draftsky, Rev Roadages, Darren Leadfoot, Ponchy Wipeout, and Murray Clutchburn. They are all replaced by next-generation racers by the time of the Florida 500.