Other mistake: After the scene where the building explodes when the gas was rerouted to the station, there will be a shot of the main bad guy staring at the computer screen saying the connection failed. On one of the two connection lost screens, it says, "connection faild", this is not how you spell "failed". (01:16:45)
Audio problem: When at the Warlock's place, McClane says something along the lines of, "What're you guys talking about?" When he does, his lips are out of sync with the audio. (01:29:50)
Audio problem: When McClane and Ferral arrive at Woodlawn, Ferral says something about the cooling towers being on the lower floors. As he does, his mouth doesn't move at all. Granted his mouth is blocked for most of it, but you can see a bit of his mouth at points and it's not moving. (01:30:15)
Audio problem: When McClane and Ferrel are confronted at Woodlawn by the bad guy, the bad guy says "You, fix it." When he does, his mouth doesn't move for "You." (01:33:00)
Continuity mistake: When confronted at Woodlawn, the bad guy is looking at McClane or Ferrel depending on the angle. (01:33:00)
Audio problem: When McClane is walking through Woodlawn and talking to Gabriel over the radio, his mouth doesn't match what is being said. (01:38:50)
Continuity mistake: At Woodlawn, after McClane takes Russo out and taunts Gabriel over the radio, Gabriel sends Rand after him, saying, "Kill this guy, and I'll give you Mai's share." But four minutes later, when Gabriel has Lucy talk to McClane on the radio, Rand can be seen standing casually against the wall behind him, even though he already left. (Timecodes from unrated edition.) (01:39:20 - 01:43:25)
Continuity mistake: When McClane and Rand fight in Woodlawn, Rand falls down through two sets of blades rotating at high speed. Once he goes through them, the blades appear to be slowing, but at the next shot, not one second later, the blades are rotating at full speed again. (01:41:55)
Continuity mistake: Throughout the film, the injury to Farrell's ear constantly changes severity. (01:42:10)
Visible crew/equipment: Just as McClane jumps down the cab of the semi, there is a quick shot where the camera shadow is visible on the semi. (01:43:05)
Continuity mistake: When the hacker pulls up the F-35s schematic, it is shown with 10 missiles outline in red, 3 on each wing, and 4 internally. When the F-35 is shown on screen, it has no weapons mounted on the wings. (01:47:20 - 01:47:50)
Continuity mistake: When talking to AV-81 Gabriel's microphone has a wire round it. The position of the wire changes instantly. (01:47:50)
Continuity mistake: When driving the semi, McClane collides with the rear of a black BMW, but when the camera shifts to a different angle the collision continues with a cut of the truck hitting a Mercedes from earlier in the scene. (01:48:50 - 01:51:45)
Continuity mistake: At the start of the chase between the HAZ-MAT van and the semi truck, McClane hits a couple of cars and seriously damages the front drivers corner of the truck. In later shots, the damage has gone. (01:48:55 - 01:51:50)
Factual error: The hazmat van is shown to be a Mercedes Benz. The problem is that in 2007, when the movie was shot, this was sold by and as a Dodge. It was only sold as a Mercedes from 2010 onwards. Presumably it was rebadged as part of a product placement deal. (01:48:55 - 01:51:50)
Revealing mistake: Just after the F-35 explodes there is a shot of the flames receding up the ramp McClane slid down. Also in this shot, Rubble goes uphill, showing the shot was reversed. (01:51:20)
Factual error: This is supposed to be an F-35B, the STOVL version with the additional lift jet. The B model has no internal guns, let alone two firing from the bottom of the air intakes. The only gun it can carry is fitted in a multi-mission pack attached to the belly. (01:54:25)
Factual error: Just after Bruce Willis slides down the ramp, and gets up to walk away, there is a car that supposedly fell off the highway. This car is turned upside down. It is obvious that the transmission and drive shaft have been removed from the vehicle, making it undrivable. (01:56:15)
Other mistake: At the end Farrell is in the ambulance and talking to McClane. When doing so his hair is perfectly clean. After being through what he and McClane have been through in the last 24 hours, it's extremely unlikely his hair would be that clean. (01:58:35)
Plot hole: Since they took down the telephone network, it would have been impossible for Justin Long to even be speaking to the emergency response woman for the car, much less send a signal to start the car up.
Suggested correction: Is it possible this is a satellite phone call akin to Onstar?
No, the BMW system requires a cell signal to work, which was taken down earlier in the movie.
