Continuity mistake: When McClane and Farrel are talking about what Farrel would do next if it was his fire sale, McClane and Farrel move closer together instantly. (00:54:00)
Continuity mistake: In the scene where McClane rebuffs Ferrell for thinking it would be cool to do the firesale, you can see pipes for firehoses right behind McClane. When the shot changes to a long alley shot, the pipes are a good ten feet away, but when it reverts back to a closeup, the pipes are back to right behind McClane. (00:55:20)
Continuity mistake: When he's talking to Ferral about a fire sale and what would be next, the cuts on McClane's face are constantly changing. (00:55:35)
Continuity mistake: McClane rips the airbag out and tosses it on the road. When they drive away, the airbag has gone. (00:57:30)
Continuity mistake: When John and Mai are fighting at the power plant, John tosses Mai up against a glass board. Her half pony tail has come undone and her hair is a big mess. You see Mai from the back as she gets up to come after John. Her hair is now neatly combed and back in a half pony tail. But as she begins to fight, her hair is once again undone and messy. (01:06:45)
Continuity mistake: After Mai kicks McClane out the window at the power hub, there is a shot of her turning and walking away. This is obviously a reused shot of when she walked away from beating up McClane only a minute or so earlier - obvious signs are that her facial bruises have vanished and her hair is perfect, and then when it cuts to her grabbing Matthew, the bruises are back and her hair is messy again. (01:07:50)
Continuity mistake: When McClane is strangling Mia, the way he holds the cable constantly changes. (01:08:05)
Continuity mistake: When the 4x4 drops in the lift shaft, Ferrel is stood by the side of the door. Then as he says "Did you see that!?" he has changed position instantly. Then he's back to the position he was in before. (01:09:25)
Continuity mistake: When McClane is on the phone to Boeman about Thomas Gabriel, the blood on McClane's hand is constantly changing. (01:12:15)
Continuity mistake: In the semi truck that John is driving towards the end of the film, one scene shows the truck has a automatic gear box control box, in another he is changing gears on a manual shift. 2 different trucks. (01:14:15 - 02:13:40)
Continuity mistake: Just after the explosion at the power centre, Farrell's hair changes from messy to neat when he says "Win? When did we start winning?" (01:14:20)
Continuity mistake: When you see all the power going off, you see the same clip being used twice. The power goes off, it shows the airport and hospital, then it shows the power going off in the same place again. (01:14:40)
Continuity mistake: When confronted at Woodlawn, the bad guy is looking at McClane or Ferrel depending on the angle. (01:33:00)
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)
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)
