Character mistake: At the beginning they refer to the G8. Russia was removed from the group in 2014, making it the G7. (00:07:20)
Character mistake: After Wade is going over the second clue in his mind and trying to figure out what part of Halliday's past is he trying to escape from, he looks over the wall of article clippings and notes he has hung up. When the camera stops on Karen Underwood's obituary, there is a hand written note beside it listing movies set in New York, with the sentence "Set in New York" underlined. This apparently him looking for clues in films set there for the race challenge that is in Manhattan. However, one of the films he has written on that list is Mad Max, which takes place in Australia, not New York. (00:35:00)
Character mistake: During an intermission following Dmitri's revenge after the attempted hit on him, the Chief of staff discusses the data with Dr. Updale. There's a pie chart in the screen in the background, and the segments are; 5%, 25%, 16%, 14% and 50%, which add to...110%. It's not a pie chart, it's a pie and a slice. (00:50:15)
Character mistake: When George throws one of the soldiers through the cockpit door of the plane, you get a brief glimpse at the pilot and co-pilot, both of which are wearing a Bose headphone/mic set. However the co-pilot has his one backwards, with the mic bent from the right side when it's meant to be on the left. (00:44:50)
Character mistake: When recruiting Burt to help repel the Graboid attack in the arctic, one of the team members says he's ideal for the job because of his experience hunting them on two continents, a reference to the first two films (Nevada and Mexico in North America) and Tremors 5 (Africa). However, this repeats the mistake in Tremors 5 in overlooking the Argentina incursion stopped by Burt at the beginning of Tremors 3, which gives him experience fighting Graboids/Shriekers/Ass-Blasters on three continents, not two. Burt, himself having overlooked Argentina in Tremors 5, does not correct her. And it's not as if the film is completely ignoring Tremors 3, since it shows the flashback of Burt being swallowed by a Graboid in that movie, which is how he got infected with the deadly parasite killing him here.
Character mistake: Immediately after the crash, when Reeves is carrying his youngest child Sophie, the actress opens up her mouth, even though she has already drowned. (00:14:43)