what happened to doc hudson in cars

In the 2006 Pixar film Cars, Doc Hudson is an anthropomorphic 1951 Hudson Hornet who is the medical doctor and local judge for Radiator Springs. After meeting Lightning McQueen, Doc reveals that he is actually a former Piston Cup racer known as the Fabulous Hudson Hornet, and returns to the Piston Cup to act as Lightnings crew chief in his races. In the subsequent films, Doc remains an important figure, and his relationship with Lightning becomes central to the plot of Cars 3. However, the films do not provide a clear explanation of what happened to Doc Hudson. In Cars 2, it is mentioned that Doc passed away before the events of the film. While there is a tribute to Doc in Cars 3, the film frustratingly fails to answer the question of what exactly happened to him.