The Following contains a minor spoiler for Cars 3.
While the Cars movie franchise is about to take its third trip around the track, the series has never really been about auto racing. The newest entry looks to be changing that by making Pixar's first "sports movie" and as such the film is going to be full of a lot of different references to actual racing including one odd little easter egg to one of the strangest parts of the history of NASCAR, Jocko Flocko, a monkey who used to ride in a car during actual races.
Tim Flock was a racer in the 1950s who, as a gimmick, used to ride around with a rhesus monkey in the car with him. The monkey, Jocko Flocko by name, became something of a mascot of sorts. I had the pleasure of hearing about Jocko Flocko during a Cars 3 press day from Cars Creative Director Jay Ward. According to him...
Tim Flock had this funny idea of having a monkey dressed up in a miniature racing suit with a miniature helmet driving in the car with him. It also did a good job of freaking out anybody who tried to pass him, they'd see a monkey in the car and freak out and pull away and he'd win.
Jocko Flocko gets a hat tip during one scene in Cars 3 that I was able to see. After Lightning McQueen is on the road to recovery following the crash you see in the trailer, he hits the road looking for places that he can train outside of the public eye. This leads Lightning to one of the old dirt tracks where his mentor Doc Hudson used to race, but since Lightning doesn't want people to know that it's him he goes in disguise. This results in Mack, Lightning's trailer, voiced by John Ratzenberger, getting himself disguised as well, as a truck advertising Jocko Flocko's Party Supplies, a reference to the former racing monkey.
This reference is the one surviving part of a series of jokes thaty had been previously planned for the film. Originally, Mack was going to find himself disguised as many different things over the course of the movie. According to story supervisor Scott Morse...
There was a running theme that they were on this kind of spirit quest. McQueen would have to kind of lay low and not be seen in the public eye so Mack was going to have to be disguised and we ran through this whole series of gags where Mack was going to be disguised throughout the whole film as they're driving around the countryside as a lumberjack or military transport or as a shipping container. At one point he was going to be a traveling circus... there was one great gag that ran for a while at the beach sequence where they're disguised as a movie crew that's on a shoot so if McQueen is seen in the world, he's an actor playing Lightning McQueen and Guido is the Italian director.