Cars 2 was the first Pixar feature-film sequel not to be part of the Toy Story series.
Released in 2011, Cars 2 followed Toy Story 2 and Toy Story 3 as Pixar's third theatrical sequel. It was therefore the studio's first sequel centered on a non-Toy Story property. The Incredibles 2, released later in 2018, was also a sequel to a non-Toy Story film, but it was not the first.
Cars 2 shifts attention toward Mater, who becomes involved in an international espionage plot while Lightning McQueen races in the World Grand Prix. This approach makes the film notably different in tone from the original Cars, which focused more heavily on Radiator Springs and Lightning's personal growth.
Cars 3 returned to a more racing-focused story and was released in 2017. It is a separate sequel, not the answer to the chronological distinction established by Cars 2.