What is the title of Pixar's first Cars spin-off series of short films?

Pixar's first Cars spin-off series of short films is Cars Toons: Mater's Tall Tales.

The series centers on Mater, Lightning McQueen's tow-truck friend, who tells stories about extraordinary adventures from his supposed past. The comedy comes from Mater's confidence and the question of whether his tales are being exaggerated.

Cars Toons began with the short “Rescue Squad Mater,” which premiered in 2008. Later episodes place Mater in settings involving drag racing, detective work, heavy machinery, and other playful versions of familiar genres.

Lightning McQueen usually appears as Mater's listener and friend. The shorts expanded the Cars world between feature films and were released through television and home entertainment formats. The title is often shortened to Mater's Tall Tales, but the full series name is Cars Toons: Mater's Tall Tales.