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.

Jeff Kinney expressed interest in making the film animated.

The short script shared for auditioners feature lines from both Hard Luck and The Long Haul.

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.

Originally Rowley was going to have a larger role in the film than in the book, in which he only appears in one flashback illustration that was in the book. However he only had a small part in the beginning and ending of the movie much like in the book. So this marks the first film where he only has a minor role. Chirag, Patty, Holly, Heather and Fregley are not shown in this film at all.

Diary of a Wimpy Kid: The Long Haul started filming on September 20, 2016 in Atlanta, Georgia and finished on November 18, 2016.

This movie uses plot elements from several Wimpy Kid books.

The actress who played the mother of Greg in the past three movies, Rachael Harris, played the mother of the new Greg, Jason Drucker, in Barely Lethal (2015).

Tom Everett Scott and Steve Zahn, who have shared the role of Frank Heffley, both starred in That Thing You Do! (1996).

Is based on book 9, however, the previous Wimpy Kid movie, Diary of a Wimpy Kid: Dog Days (2012) was based on book 4, the franchise skipped books 5-8.

The song which the parents love from when they were dating is "Wannabe" by the Spice Girls.

While on the Alien Abduction, Greg begins climbing away from Mr. Beardo. Greg accidentally hits a girl with two braided pig tails in the head with his knee. The girl says, "Watch it you jerk!" Her sharp attitude along with her hairstyle resembles Patty from the previous films. However it is not confirmed that this character is her, as she is unnamed in this movie.

The scene where Greg Heffley is caught in the hotel shower by Beardo parodies the infamous shower scene in the movie "Psycho" (1960).

Several of the cards in the game the Hefleys play foreshadow events they get into, such as owning an unusual pets or meeting a celebrity.

In Diary of a Wimpy Kid 8: Hard Luck, Meemaw is dead. However, this film is based on Diary of a Wimpy Kid 9, after the events of Hard Luck, and says that she is still alive.

At the end of the film Greg Heffley narrates and says, "I can't wait to see where we're going next year!" Susan Heffley then chimes in by saying, "Wherever it is, we're flying." Although this film is based on the ninth book in the series, about six months after this film released, another book was added to the series entitled "The Getaway." This book is the twelfth book in the Diary of a Wimpy Kid series by Jeff Kinney. In this book the Heffley family goes on another trip by means of an airplane!

In a gamer expo scene some of the chairs in a booth are from the Hunger games series