Dinoco is the fuel company sponsoring the Piston Cup in Pixar's Cars.
Dinoco is represented by a bright blue color scheme and a tyrannosaurus logo. In the first Cars, its sponsorship is highly desirable to Lightning McQueen and Chick Hicks, helping motivate their competition during the Piston Cup season.
The Dinoco sponsor is closely associated with The King, a veteran race car whose real name is Strip Weathers. After The King retires, Lightning receives a Dinoco sponsorship offer, but he chooses to remain with Rust-eze, the brand that supported him at the start of his career.
Rust-eze is therefore a major sponsor in the film but is not the Piston Cup's sponsor. Octane Gain is another fictional racing brand in the Cars universe. Dinoco also appears in other Pixar films as a recurring fictional company, creating a visual connection across Pixar's worlds.