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In the opening scene, if you look closely at the Highway 9 Sector 26 sign. There is a date written on the sign: December 6th 1984 and the MFP sign at the Halls of Justice also has a date on it: MFP Established in 1983. Even though these signs were canon to the film. George Miller said during an earlier interview in the exact same year of 1984, Mad Max is set in 1997 and Mad Max 2: The Road Warrior is set in 1999.
Most of the extras used in the film were paid in beer.
The "get-out-of-jail-free card" that Goose gives the triker was an on-set joke. Because of the limited budget, the biker gang was an actual biker gang (the Vigilantes), and they had to ride to the set each day in-costume; often with their prop weapons displayed. Since the production company expected them to be pulled over by the local police, each was given a letter explaining the film's peculiar requirements, and asking for law-enforcement's understanding and cooperation.
Tim Burns (Johnny the Boy) was so into character that he annoyed everyone on-set, and was abandoned one day during lunch while handcuffed to the wreck.
Some of the things Nightrider yells over the radio are lyrics from the AC/DC songs "Rocker" and "Live Wire."
James McCausland: The bearded man wearing an apron in front of the roadside diner watching the police cyclists and tow trucks drive away is the film's co-writer.