Michael Wallis, who has provided voice work on Pixar's two "Cars" films so far, has revealed that a third film in the series is in the works.
Giving a radio interview with Illinois station WGBZ, Wallis said: "Cars 3 we’re coming back to the road. And we’re coming back to 66 into 99. That’s the road that runs right through Central California."
Wallis is also a historical consultant and recently authored the book "Route 66: The Mother Road" so knows quite a bit about that subject matter.
Neither Pixar or Disney have officially made any suggestion of a third "Cars" film at this point, aside from a comment by Disney's Bob Iger of an unnamed "sequel" besides "Finding Dory" being in the works for release some time in the next few years.
The "Cars" films are the worst reviewed franchise released under the Pixar brand, yet they are also amongst the most profitable due to the billions in merchandising they rake in for Disney.
Source: Screen Crush