As previously mentioned, in one of the flashback sequences in “F9,” young Dom attacks Kenny with a wrench, and the choice of weapon isn’t a random one. Before Dom even gets there, Jakob picks up a wrench to attack Kenny first but stops when his brother intervenes.
While any tool would have done the job, there’s a specific reason the Toretto boys use a wrench. This small detail falls in line with a “Furious 7” scene in which Dom and Deckard Shaw (Jason Statham) have an over-the-top fight where the former battles his opponent with the tool. He also pulls out a massive wrench earlier in the film to fight Shaw on a separate occasion, but Mr. Nobody (Kurt Russel) stops the fight before it gets physical.
Additionally, in “Fast Five,” Dom wields a wrench at the end of an epic fight with Luke Hobbs (Dwayne Johnson). Just when he’s about to hit Hobbs in the face, Mia screams at her brother, and he drops the weapon next to his adversary. When it came to selecting a weapon for the young Torettos in “F9,” there really was only one way to go.