In Pixar’s Cars 3, Cruz Ramirez becomes Lightning McQueen’s main racing trainer.
Cruz is introduced as a highly capable trainer at the Rust-eze Racing Center. Her work emphasizes modern technology, simulation, fitness, and data analysis, methods that initially frustrate McQueen because they differ from the older style of training associated with Doc Hudson.
Their relationship changes as McQueen recognizes Cruz’s own unrealized potential. She is not merely a coach who helps him return to competition; she is also a racer with the talent to compete at the highest level. The film’s conclusion develops this idea by allowing Cruz to take a more prominent place in the racing world.
Sally Carrera is McQueen’s romantic partner and a lawyer, while Flo runs the local café in Radiator Springs. Miss Fritter is a demolition-derby competitor, so none of those characters is McQueen’s principal trainer in Cars 3.