Bruce Willis was set to reprise his role of Mr. Church, at a salary of $3 million ($750,000 per day for four consecutive days). When he demanded $1 million per day instead, Sylvester Stallone and the producers refused, and he left the film. Within three days, Stallone was able to get Harrison Ford to replace the Church role as a new character. Ford's "short notice" quip, as used in the trailer, alludes to these events (which were well publicized long before the film premiered).

While shooting an action scene in a truck, Jason Statham almost drowned when the truck fell into the sea after brakes failed.

As his character in the film, Harrison Ford is a skilled pilot in real life. In fact, Ford has conducted some search-and-rescue missions, just like his character does in the film.

When he is asked about the whereabouts of Church (portrayed by Bruce Willis in the two previous films), Max Drummer (Harrison Ford) answers that "He's out of the picture." This is an in-joke about the fact that Willis' character was written out of the film and replaced with Ford's character.

Sylvester Stallone tried to get Wesley Snipes to play the role taken by Terry Crews in The Expendables (2010). Crews went on to play Hale Caesar after Snipes declined due to legal matters related to his tax-evasion charges that prevented him from leaving the United States without the court's permission. Wesley Snipes got the role as "Doc" shortly after his release from prison. In a scene, Dolph Lundgren's character asks Snipes' character what he was locked up for to which he replies "tax evasion".

Continuity

In the first Expendables movie, Lee Christmas has his Expendable tattoo on his right forearm. In this movie it's on his left forearm.

After being rescued from the prison transport, Doc tells the other Expendables that Barney still hangs up the dog tags for deceased members in the plane as a memorial. In the second movie, the original plane crashes and gets buried in the mine. Those original dog tags would have been on that plane and not the new one. It is possible, though, that Barney would have made new ones to keep the memory of the fallen alive when he was outfitting the new plane.

During the final action scenes when the biker rides up the plane tail, he hangs on to a metal rod with one hand and fires at the enemies with the other hand (his helmet fully on) swings and when he lands in the next shot, he has no helmet on.

(at around 1h 19 mins) When the plane is taxiing before leaving for the rescue mission and pulls up in front of Barney's old team, both propellers are standing still, despite rotating in the shots before and after.

At the start of the film Gunner, Christmas and Toll climb onto a helicopter. When the helicopter is in the air, they have switched sides. (i.e. Gunner is on the left side of the chopper on the ground but the right side in the air)



Factual errors

The helicopter of Conrad Stonebanks bears the roundels of the Bulgarian Air Force and not of the Somali Air Force. Filming was done in Bulgaria.

Barney's plane is Russian AN-26 which is a turboprop, but the sound it makes is of piston aircraft. Also, AN-26 cannot fly from New Orleans, LA to Bucharest, Romania without refueling.



Revealing mistakes

The bomb that Stonebanks drops from the helicopter during the opening battle is a Mk82 Snake Eye, a high drag version of the Mk82 Bomb. These bombs are unguided. The fins that deploy when it is dropped are only used to slow the bomb down for high-speed, low-altitude deployment. They do not fly the bomb to its target. When dropped from stationary helicopter, it should have dropped straight down and missed the team entirely - instead of flying towards the team and landing on the truck.

When Bonaparte is first showing Thorn to Barney, Thorn is rock climbing, He slips, falls, and deploys a bright blue parachute. When the scene cuts to Thorn landing someplace behind Barney and Bonaparte, the parachute is red.

When two of the Expendables walk across the glass roof of the art museum, an assault rifle is just lying there near the building edge, for no apparent reason.



Miscellaneous

Just before the 50 min mark, Lee Christmas throws a knife, after seeing where the knife ends up the camera pans back round which sees Lee walking away. The camera cuts back towards knife, then back to Lee, who is now standing in the position where he threw the knife from.

The team is arriving in Bucharest and jumps off the plane. In the next scene the team is in the center of Bucharest. There was no need to jump off the plane with parachutes, they could easily land and proceed to their mission.

When Barney is hanging from the helicopter near the end, the view is from inside the helicopter with the skid below. Barney should be hanging out of site below that, yet is hanging from a point away from above the door on an angle that would only be possible if the rope was attached to an outrigger arm at least 20ft away to the side of the helicopter. The winch used would be barely a few feet clear of the door and most likely visible from this point of view.



Anachronisms

During the assault on the waterfront Doc jumps onto the roof of a passing truck. There is an armed guard walking behind the truck a short distance back, walking in the same direction. The guard would have easily seen Doc's movement and raised the alarm.



Errors in geography

When Barney Ross and Bonaparte go to the appointment with Galgo, a caption says they are in Arizona. When they leave the car the license plate is from Spain.

The Haval has European vehicle registration numbers 3052 CFS with the blue European colors on it.

The meet between Stonebanks and the buyer is supposedly set in Moscow, but the signs at the entrance are in Bulgarian.



Character error

Stonebanks tells Vata that X-rays damage the oils in artwork, and therefore customs doesn't scan them. X-rays are actually frequently used to examine paintings. This is the method by which changes made by the artist, rough sketches, or even completely other works, are discovered underneath.