The stunt involving the flatbed truck slamming into the moving train was filmed practically, without the use of miniatures or CGI. The collision nearly derailed the train, as can clearly be seen.
Vince's right arm, which can be seen in the train heist, has scarring. This is because of the truck heist attempted in Fast and Furious (2001), in which Vince's arm is cut by a metal wire.
When the team steals the four Dodge Charger police cars to do a drag race, the police lights on one of the cars turn on. According to car co-coordinator Dennis McCarthy, Dodge had just released that particular model of the Charger and as a result, some of the cars used were still prototypes. The police lights activating was a malfunction on that particular car and wasn't in the script. After filming, they decided to keep the scene intact because it was thought that that's what Roman (Tyrese Gibson) would have done anyway.
The role of Hobbs was originally envisioned for Tommy Lee Jones. According to Vin Diesel, Dwayne Johnson was brought into Fast Five because of a fan suggestion from a girl named Jan Kelly, who said she would love to see the two work together on screen.