Cars 2 was Pixar's first sequel not belonging to the Toy Story series.
Released in 2011, Cars 2 followed Toy Story 2 and Toy Story 3 as Pixar's third feature-length sequel overall. It was also the studio's first sequel outside the Toy Story franchise. The film shifted the series toward international espionage, with Mater becoming involved in Finn McMissile's investigation during the World Grand Prix.
Finding Dory was Pixar's second non-Toy Story sequel, arriving in 2016. Cars 3 followed in 2017, so it was not the first film to establish this expansion of Pixar's sequel strategy. The distinction concerns feature-film sequels: Pixar had already made many short films and other connected projects before Cars 2.