Because the release dates of this film and the previous Diary of a Wimpy Kid film are so spaced apart, child actors such as Zachary Gordon from the previous films did not reprise their roles due to being too old for their characters. Also many of the adult actors had begun working on other projects. So it was the easiest decision to invite an entire new cast for the film.
Many fans of the franchise expressed a lot of anger at all the recasting for this film, especially when it came to Rodrick, spawning the popular meme "#notmyrodrick", a parody of the "#notmypresident" trend that became popular after the election of President Donald Trump.
The short script shared for auditioners feature lines from both Hard Luck and The Long Haul.
The scene where Greg Heffley is caught in the hotel shower by Beardo parodies the infamous shower scene in Psycho (1960).