In Pixar's Cars 3, Cruz Ramirez is the young racing trainer hired to help Lightning McQueen.
Cruz works at the Rust-eze Racing Center, where she trains racers with advanced equipment and data-driven methods. Lightning initially resists her coaching because he wants to recover his speed through traditional experience. Their relationship changes when Cruz shows that she understands racing and has ambitions of her own.
Cruz is not merely Lightning's mechanic or pit-crew member. She is a skilled trainer who later becomes a racer in her own right. Sally Carrera is Lightning's longtime friend and the town attorney, while Natalie Certain is a statistical analyst who evaluates racing prospects. Mack remains Lightning's transport truck, so none of those characters fills Cruz's role.