In The Ballad of Gay Tony DLC mission, "Caught With Your Pants Down", Luis was originally supposed to meet Yusuf in Westminster to pick up his Buckingham Swift helicopter. In the final game, Luis meets Yusuf at Star Junction, and he already has the helicopter.

There are animations, a model and texture related to an unused wooden plank weapon that NPCs would have carried, specifically by the dockworkers at East Hook. An NPC can be seen holding this plank in the first trailer for the game.

An update released three days before the game's 10th anniversary on April 26th, 2018 added new songs to radio stations, while simultaneously removing songs due to licensing-expiration issues. Among the many song replacements, the Electro-Choc, Fusion, JNR, Massive B, and Tuff Gong radio stations remained untouched, while almost every song featured in the Vladivostok FM station was cut and replaced with new songs with one exception, "Liberty City: The Invasion" by Seryoga, an original song written for the game's soundtrack. These changes also carried over to the Episodes from Liberty City DLC expansions.

There are unused strings of text in The Lost And Damned referencing a cut mission for Stubbs. In the mission, Johnny had to blow up a truck with a bike armed with a bomb that would arm itself at 88mph, but would explode if your speed dropped below 88mph.

The mission may be a reference to the movie "Speed", which features a bus armed with a bomb that detonates if dropping to a certain speed. A mission with a similar concept was present in Grand Theft Auto: Vice City.

The Australian console versions of the game originally censored many features, including shortening prostitute pickups and removing the animations, as well as removing any blood from shooting NPCs, or the player being damaged. These changes were reversed after the PC version was released.

There's a glitch at the Windmill Street Station's southern platform. If the player hits a pedestrian and tumbles into either side of the stair barrier, said pedestrian will begin to start twitching and contorting violently.

Companion characters have no crash animation for when they are talking on the phone.

If you stay still on the step 2 of the Higgins Helitours Heliport's ladder and the NPCs try to climb up, a glitch will happen where said NPC will be sent flying away.

There is an unused variant of the website PeepThatShit.com which refers to Outlook Park as Overlook Park.

In the 2009 edition of The Guinness Book of World Records: Gamer's Edition, Grand Theft Auto IV is credited as the "Largest Voice Cast in a Video Game" with 861 voice actors: 174 individuals voicing the main cast and voice-overs and the remaining 687 were mostly volunteers who wanted to be part of the game in some way.

There were two cut random character missions in The Ballad of Gay Tony. They both involved Luis running into ex-girlfriends. One mission has Luis taking the ex-girlfriend home and defending himself from her brothers, while the other involved the ex planting a bomb in Luis' car. It is unclear if these missions involved the same girlfriend, or two different ones.

The Rhino was originally going to appear in the game, but it was cut. There are still lines of code within The Lost and Damned files that show this.

If the player changes the theme background of their cellphone, the background of NPC cellphones will change as well.

If the player selects the Uzi while inside a car and then uses the advanced weapons cheat code, Luis will be equipped with the Assault SMG inside the car. Because this was not originally intended, firing the weapon will cause a glitched animation.

Johnny holds the automatic 9mm upside down while shooting from a car.

If the players spawns a cab inside a safehouse with the use of a trainer, then proceeds to enter the cab a select a destination, the destination will also appear on the TV screen.

If the player tries to hire a hooker using a cop car, an ambulance, a bus or a fire engine, Niko will say that the car is too small.

If the player gets a wanted level of 1 or 2 stars while driving on the bridge while an Annihilator Helicopter is flying nearby, it show up as a police helicopter on the radar.

If the player kills a gun store owner and comes back to the same store later, the new gun store owner will try to kill them. If there isn't a new attend three other gun store owners from different stores will appear and attack the player; sometimes this happens right after killing a gun store owner.

If the player is on a mission with Little Jacob and both get into a convertable car while Jacob is smoking, a glitch will occur where Jacob jumps into the car without using his arms.

Both the pump shotgun and sniper rifle fire faster and deal more damage when the player is rapidly switching between the crouching and standing positions.

Originally, TW@ was able to sell food and had a larger selection of staff. Audio associated with this unused feature still exists within the game's files.

According to a website made by prop artist Gill Bertram, there was going to be another accessible bank in Liberty City based on an unnamed New York bank. Additionally, the same website features a screenshot from the beta that shows a slightly different HUD and a different font for the money counter.

A café restaurant called Rockstar Café was cut and was renamed Superstar Café; however, the beta name is still on the employees outfits. More evidence of the original name can be found in the game files.

If the player is driving on the Algonquin Bridge while there is a train underneath it, a glitch will cause the cars to swerve out of the way even though the train is under the road.

Roman Bellic is the only character in the game that speaks to all three protagonists from GTA IV and its DLC's. In GTA IV, he is the deuteragonist to his cousin Niko Bellic. In The Lost and the Damned, he speaks to Johnny when he is kidnapped by him in the mission "Roman's Holiday". Finally, in The Ballad of Gay Tony he interacts with Luis Lopez outside of the entrance to the Maisonette 9 club in the mission "Ladies Half Price".

Spoiler:In the mission "Final Interview", the player goes to a lawyer's office to retrieve some files from a lawyer named Tom Goldberg who complains about how violent video games are corrupting young people, the player must then kill Tom to continue the mission.
This is a reference to now disbarred lawyer, Jack Thompson, who threatened legal action if changes weren't made to the mission. The developers didn't change anything, and Thompson never followed through on his threat.

The users "Oscar Wild" and "MALCOLMseX" on love-meet.net are obvious parodies of Oscar Wilde and Malcolm X, respectively.

There is leftover text which suggests that during "Bull in a China Shop" Niko was supposed to beat up the shop owner's son. The son does not appear in the final game at all.

The game files suggest that at one point during development Niko was supposed to drive to a food vendor during "The Cousins Bellic".

During The Ballad of Gay Tony's mission "In the Crosshairs", the building that Luis was on was supposed to catch fire, leaving him to find another way to escape. There are still text strings that reveal this.

The game has two unused maps in its files. One is called TestCJ, and the other is called AnimTest. Many of the shows in game are filmed in special areas in TestCJ, and an unused pedestrian can spawn there.

In 2010, a lawsuit was filed by Brazilian composer Hamilton Lourenço da Silva with the Civil Court in Barueri against Rockstar Games and Synergex Brazil to restrict trading and distributing of Episodes From Liberty City in Brazil, and Worldwide, due to the song "Conga Kid", which is featured in The Ballad of Gay Tony, having sampled from his song "Bota o Dedinho pro Alto" without his permission. The injunction stated that a fine of R $5,000 (US $3,000) would be issued for each day the expansion was continued to be sold.

In The Lost and Damned, there was originally a skate park, but it was cut. You would not use a skateboard, but instead a motorcycle. There are still files hinting at its existence.

In The Ballad of Gay Tony, there was going to be a completely new vehicle introduced, the Robin, before it was scrapped. The only existence left of it is some handling files.

The third trailer for the game shows that Mikhail Faustin originally had grey hair and a different hair style.

Both Roman's clothing and hairstyle were changed during development, as seen in a pre-release screenshot.

The "Vlad Glebov" trailer for the game shows a black variant of the Taxi, which is never seen in the final version.

Niko's default outfit did not have a white stripe on the collar during development. This can be seen in multiple pre-release screenshots.

During development Ilyena Faustin wore different clothes, which can be seen in the second trailer for the game.

The second trailer for the game shows that Real Badman didn't originally wear a hat, unlike in the released version.

Originally in The Lost and Damned mission, "Politics", Johnny was supposed to get a uniform to pass by security. This also means that Johnny may have been able to have changed outfits in development.

The Fight Club was originally going to be introduced in The Lost and Damned, but it was cut until The Ballad of Gay Tony. There are still files referencing it in The Lost and Damned.

Female police officers were originally going to be implemented in the game before being cut. One can be seen in the first trailer for the game.

During development Michelle had a different face to the release version, as seen in the "Move Up, Ladies" trailer.

In the PC version of the game, the cook on the ship at the beginning of the game has a full beard; however, in the console versions of the game, he is clean shaven.

In the mission, "Wrong is Right", an email from a "Larry Ligner" sent from ligner@goldberglignerandshyster.com can be found on Oleg Minkov's computer. This would suggest that Larry was an early name for Patrick Ligner.

In The Ballad of Gay Tony, during the mission, "Boulevard Baby", a low quality map of Salem, Massachusetts can be seen on the desk in Vic's office.

During the mission, "Clean Getaway", while Niko and Vlad are walking to Vlad's car, Vlad is nearly hit by a Taxi and yells "I'm walking here" at the driver. This is a reference to a scene in the film "Midnight Cowboy", in which Dustin Hoffman is almost hit by a taxi and yells the same phrase. It may also be a reference to the film "Back to the Future Part II", in which Martin McFly Junior is almost hit by a car while crossing the street and yells the same phrase repeatedly.

The GPS usually makes an instrumental "bing bong" sound when approaching a turn. On rare occasions, the voice will actually say, "bing bong".

There are unused textures for Tony, Mori, and Brucie's names for when playing darts in The Ballad of Gay Tony. This implies that they could all be taken out for friend activities at some point in development.

A restaurant was planned to appear in the game called "Ping's". Audio associated with the restaurant still exists within the game's files.

There are multiple sound files for a golf kart in the original game, meaning they could have been planned to be implemented before the Ballad of Gay Tony.

The game was at one point going to have bus drivers. They were cut for unknown reasons, but they appear to be fully modelled.

Originally, Little Jacob did not wear glasses.

Mickey originally didn't wear glasses and wore a different outfit.

The pistol's chamber was originally black instead of grey.

According to an interview with Dan Houser by the Official Playstation Magazine UK, Staten Island was not included in the game because the development team decided that it wouldn't be a fun location to play in.

Originally, ice cream could be bought from street vendors. Sound files still exist in the game's data.

There was originally a restaurant named "Fanny Crabs" which would be based off of the real life restaurant, "Fatty Crabs". Sound files still exist for the workers. The name is also British slang for pubic lice on a woman's genitals.

Graphics for a scrapped game mode called "Zombie Revolution" can be found in the game's files.

There are sound effects for a handheld minigun in the game's files.

In earlier versions of GTA IV, one of the Most Wanted criminals, Maxwell Caughlin, is listed on the database as Maxwell Caddy.

The Wooden Baseball Bat was originally going to be included in The Lost and Damned, but was cut.

There is an unused pinball animation in the game's files, meaning that pinball was likely planned to be playable at one point.

In the Ballad of Gay Tony mission "Not So Fast", the Jewish mobster who attempts to shoot Luis in the cutscene has a Pump Shotgun, but after the cutscene, the shotgun lying on the ground is the Combat Shotgun.

In the Ballad of Gay Tony trailer titled "Meet Luis Lopez", Luis is seen wearing the brown and black Perseus suit, but with blue jeans. This implies that it may have been one of Luis' already available outfits.

Cash registers throughout the game have a button that reads "Ask CJ". This is visible through the use of a sniper rifle, zooming in on the keypad of the cash register. This is a reference to CJ from Grand Theft Auto: San Andreas.

The multiplayer mode "Bomb Da Base II" pays homage to the GTA III mission "Bomb Da Base Act II". In both, the player must collect explosives and place them on a ship.

There are signs that the Well Stacked Pizza Co. from Grand Theft Auto: Vice City and Grand Theft Auto: San Andreas was originally meant to reappear in the game:

• Outside the store "Pizza This", the employees are still seen sporting the logo and some with "Well Stacked Pizza Co." on the back of their shirts.
• Logos and names of Well Stacked Pizza can be found at a shuttered storefront at the Alderney Casino in Westdyke, Alderney.
• The chain is mentioned on the Pißwasser website as a business partner of the beer company.
• When blocking the route of certain taxis, the driver will sometimes shout lines such as "Hurry up, I need to get to Well Stacked!" and on occasion "My Pizza Stack's gettin cold, move it!"
• Pedestrian-to-pedestrian dialog will occasionally involve whether Pizza Stack or Burger Shot is better.

During one of the powerboat outings with Brucie Kibbutz, he will call the Statue of Happiness the "Statue of Freedom", while the subtitles still say "Statue of Happiness." This suggests that the statue might have had a different name during development, but the audio file did not get changed to reflect the statue's final name.

The achievement/trophy "Finish Him" is a reference to the Mortal Kombat series, in which the announcer says the same phrase at the end of the final match.

The achievements/trophies "Join The Midnight Club" and "Top The Midnight Club" are possible references to the Midnight Club series which is also by Rockstar Games.

An MP5 was originally going to be the SMG as seen in early pre-release screenshots. It had a 15 round magazine. An image of Niko holding it confirms this. Niko would presumably fire it with both hands on the pistol grip, like the Micro SMG. Its design was later replaced to resemble the S&W MP10.

The setting of the game was originally going to be Liberty State, rather than just Liberty City, and it would have included countryside surrounding Liberty City, mountains based on the Adirondacks and Catskills, and possibly The Caraways.

In multiplayer, if one player kills another with a vehicle, the HUD may say that they "gouranga'd" the other player. This is a reference to the original Grand Theft Auto, where if the player runs over a line of Hare Krishnas, they get a Gouranga bonus.

Internal files call the Beechwood City area of Broker "Grayfords", suggesting that Grayfords was Beechwood City's original name.

An unused map icon representing a boat can be found in the game's files. Its file name is radar_boattour, suggesting that a boat tour service was once available in the game.

The pool cue from the pool mini-game is categorized as a weapon, but cannot be acquired outside the context of the mini-game, and thus cannot be used as a weapon. It has all the necessary data, including a HUD icon.

In the third trailer for the game, "Move Up, Ladies", the mission "The Cousin Bellics" is shown during the day while in-game the mission takes place at night.

There are two scrapped haircut designs in the game: one resembling helmet-hair, and the other a buzz cut. These still exist in the game's data and can be modded in.

During the introductory cutscene of The Lost and Damned, while The Lost Brotherhood are riding in formation down the streets of Liberty City, Niko Bellic can be seen walking on the sidewalk in his default attire, bumping into a pedestrian and speaking in Serbian to the person. Niko's cameo appearance in Alderney is somewhat incongruous, as he would still be confined to Broker and Dukes during this mission of The Lost and Damned.

References to conditions relating to snow can be found in the game's files. This suggests that snow was considered as a weather condition at one point during development.

There are references within the game's data files to a nightstick weapon, but no such weapon is available in the final game.

Many street names in Bohan are named after prisons, such as, Leavenworth Ave, Alcatraz Ave, Sing Sing Ave, Guantanamo Ave, Attica Ave, San Quentin Ave, Folsom Way, Rykers Ave, and Joliet Street.

The achievement "Warm Coffee" is a reference to the controversial "Hot Coffee" mod for Grand Theft Auto: San Andreas.

The achievement/trophy "Auf Wiedersehen Petrovic" is a reference to the British comedy-drama, "Auf Wiedersehen, Pet".

If Playboy X is killed, it is possible to go to his apartment and open the wardrobe to get a change of clothes that look like the outfit worn by Claude, the protagonist of Grand Theft Auto III.

The name of the mission "The Master and the Molotov" may be a reference to the novel "The Master and the Margarita" by Mikhail Bulgakov.

A Zastava M70 was supposed to appear in game, but was most likely replaced with the AK-47. It can be seen during the second trailer for the game, "Looking For That Special Someone".

The achievement "Assassin's Greed" is a reference to the Assassin's Creed series.

The name of the mission "I Need Your Clothes, Your Boots and Your Motorcycle" is a reference to Terminator 2, in which Arnold Schwarzenegger says the same line.

It was originally intended for the game to include flyable planes and jets, however according to a Q&A session by Rockstar Games, they were cut because the map was too small.

An entry for a flamethrower exists in the game's WeaponInfo.xml file, but only the title "FTHROWER" remains, with no extra data to make it playable.

If a pirated copy of the game is recognized, the in-game camera will swing wildly around during play.

An early pre-release screenshot of Playboy X depicted him wearing a different colored sweater.

On the in-game website Yourmexicandoctor.com, two fictional drugs named Hingmyralgan and H4PP1 are listed. These drugs were first found in Manhunt 2, also by Rockstar Games.

In The Lost and Damned, in the mission "Heavy Toll", Johnny refers to the Assault Shotgun as "an American firearm". He is only partially correct, because the Street Sweeper is a copy of the South African Armsel Striker, produced under license in America by the Cobray Company.

In The Lost and Damned, when calling Jim for an Automatic 9mm, Johnny will call it a 'semi-automatic 9mm' instead.

The mission "Weekend at Florian's" is a reference to the comedy movie "Weekend at Bernie's". Not only is the name similar, but during the mission, Florian insists that he has changed his name to Bernie.

In the golf course located in Firefly Island, one of the holes has a scaled-down model of the Ocean View Hotel from GTA Vice City.

On the road between Dukes and Charge Island that passes over East Borough Bridge, the first building on the left has graffiti with paintings of past GTA characters such as Misty and 8-ball in his convict outfit.

Triads can be heard to say "My cousin owns a casino in Las Venturas; maybe we should go sometime", which is likely a reference to Wu Zi Mu and his casino in Grand Theft Auto: San Andreas.

Niko is referenced in an episode of the TV series "Criminal Minds". In the episode, a criminal states that his name is "Niko Bellic" in his personal information. An agent catches on, and tells his superiors: "Niko Bellic is the name of the main character of Grand Theft Auto IV."

The "Pager" ringtone on Niko's cell phone is the pager sound from Grand Theft Auto III.

In the mission "Three Leaf Clover", it is possible to kill Luis before escaping the bank, which would logically make the events in The Ballad of Gay Tony impossible, as in the mission "Not So Fast", Luis ambushes the diamond exchange. Moreover, the player receives no penalty for killing Luis, unlike most other missions where it is possible to kill other playable characters.

In the DLC, The Ballad of Gay Tony, Yusuf claims that the Gold SMG is solid gold, but this would make the gun very heavy, and gold would be too soft for the internal workings of the gun.

There were plans to include a Silenced 9mm Pistol in the game, but it was cut from the final build.

In The Ballad of Gay Tony, the ejection port on the Automatic Shotgun is on the wrong side in the HUD icon.

The beta version of the Assault SMG, seen in the debut trailer, lacks the suppressor and has a different firing sound. Additionally, the filler/foam in the Assault SMG's gun case in Armando's SUV does not have a cut out for the suppressor.

Despite the fact that the player gets a Combat Shotgun upon entrance in an LCPD or NOOSE vehicle, the LCPD and NOOSE officers use Pump Shotguns, with the exception of the mission The Snow Storm.

The Assault Shotgun is based on the Cobray Street Sweeper. When it is being reloaded, Johnny or the multiplayer character will be seen removing the magazine. In reality, the Cobray Street Sweeper's magazine is fixed to the gun and each shell must be loaded individually into it.

A revolver was originally going to be featured in game, and can be vaguely seen in a pre-release screenshot.

By standing next to Packie and correctly positioning the camera, it's possible to see that he has a box with skulls inside his head.

In an early version of GTA IV, a wooden baseball bat appeared. In the final game there are only aluminium bats.

The bullet casings of the Assault SMG do not fall out from under the grip of the gun like its real life equivalent, the Belgian FN P90. Instead, they fly out of an invisible ejection port on the right of the gun.

Both sides of GTA IV's MP5s feature "MADE IN SCOTLAND" markings (mirrored on the left side), alluding to GTA IV's Scottish developer Rockstar North.

Songs from a couple of radio stations in Liberty City Stories also appear in Grand Theft Auto IV in the form of ringtones. Six ringtones originate from the Lips 106 radio station, and three are from the Head Radio station.

In the Underground Cage Fighting minigame in the downloadable DLC, The Ballad of Gay Tony, spectators can be heard saying, "Sweep the leg, Johnny!" This is a reference to the movie, "The Karate Kid."

On the staircases in most apartment blocks in the game, some graffiti pay homage to past protagonists set in GTA III canon (Claude, Tommy Vercetti, Carl Johnson, Toni Cipriani, and Victor Vance) in the form of scribblings of their names on the walls.

Binco from Grand Theft Auto: San Andreas was meant to appear in the game, but was replaced with the Russian Clothing Shop. You can see it in the "Looking For That Special Someone" trailer.

Judging from the audio file names, 'Tuff Gong Radio' was supposed to be called 'Babylon', and 'The Beat 102.7' was to be 'Beat 95'.

Niko Bellic, one of the game's protagonists, was based on the character Sasha from the 2001 film "Behind Enemy Lines" played by Vladimir Mashkov. Mashkov was even asked by Rockstar if he'd like to play Niko Bellic but, declined the offer.

The Dodo was at one point meant to appear in GTA IV. Some of the Dodo's handling data can still be found in the game's files.

When the player answers his cell phone while driving a bike, he uses his right hand. In reality, this would disable his ability to accelerate, as the throttle is located on that side; in the game, the player is somehow still able to operate and accelerate the bike while talking on the phone.

Despite appearing in Promotional Artworks and Early Screenshots, Nikos fingerless gloves are not found in-game. However, they are still in the game's data and can be obtained through mods.

Going to the website "Littlelacysurprisepageant.com" from a computer in-game will get you an automatic five-star wanted rating. The website's address is a reference to the Grand Theft Auto: Vice City Stories radio commercial "Little Lacy Surprise" featuring Jack Howitzer.

Inside the Statue of Happiness, behind a door with a sign saying "No Hidden Content this way", is a large beating heart.

In The Lost and Damned expansion, a car called Rhapsody can be found in Alderney and Bohan. The Rhapsody is based off of an AMC Pacer, the model driven by Wayne and Garth in the movie, Wayne's World. The car's name is a reference to the scene in which Wayne and Garth sing the Bohemian Rhapsody song in Wayne's World. The front of the Rhapsody features a 'W' for its badge, indicating Wayne's World, and on the inside of the car in a picture of Wayne and Garth.

The official artwork for Lola Del Rio (which was used to promote the game) shows her with six digits on one hand; five fingers and a thumb underneath.

Grand Theft Auto IV previously held the record for being the most expensive game to develop, coming in at $100 million. The record was previously held by Shenmue, at $47 million, and is now owned by Grand Theft Auto V

According to the Liberty City Police Department's database, Niko Bellic's first criminal offense was "Grand Theft Auto" in 2008, the same year that Grand Theft Auto IV was released.