Certain cars that have the option to add spoilers will either add or reduce the car's downforce, meaning the combined effect of air pressure and gravity pressing down an object toward the ground and increasing its stability, and in the case of the cars in Grand Theft Auto V, reducing the object's airtime:

•Feltzer: spoilers add significant downforce.
•T20: active spoilers create significant downforce, damaged spoilers take away that downforce.
•RE-7B: stock spoilers have little downforce; prior to the Grand Theft Auto Online: Gunrunning DLC, custom spoilers gave significant downforce, but this has since been reduced.
•X80 Proto: spoilers add only a little more downforce on their own, but gets significantly more downforce when braking while the flaps are active.

According to video game researcher Liam Robertson, Rockstar Games considered porting the game to the Wii U as they were at one point creating a prototype for the system's hardware, but it was soon scrapped due to the Wii U's poor sales. In an interview with IGN, Dan Houser was asked whether the game would receive either a PC or Wii U release:

"Everything else is up for consideration, that's all I can give you. The main thing is we are not...we are a third party publisher. We're not Nintendo, we're not Sony, We're not Microsoft. We love all of them in different ways. But we can do what we want wherever there's the appropriate business opportunity and chance to find a market. If that's on Apple we put something on Apple. Wherever it might be. I think that's the fun in what we do. We see ourselves as a content company that uses technology. We don't make it; we use it to make the most fun stuff"

Former Nintendo president Reggie Fils-Aime was soon asked about the company's attempts to provide action-based games for its fan base, to which he responded:

"In the end, it is Nintendo’s responsibility to have a large installed base, to have development tools that help the developers and publishers create great content, and essentially create an environment where teams like Rockstar can bring their very best content to our platform, and if we do that hopefully the very best content throughout the entire industry will show up on Wii U."

If the player goes near Raton Canyon at Chiliad Mountain State Wilderness between 19:00 and 20:00, they'll see a car parked on a cliff road surrounded by police vehicles that'll drive off the cliff when an officer approaches it. This is a reference to the end scene in the 1991 movie Thelma & Louise.

The script for Grand Theft Auto V was 3500 pages long. In Ned Luke's own words:

"It’s a brilliant script. Dan [Houser] and Rupert [Humphries], the writers, are prolific. You have to understand, this is a 3500 page script, it’s unbelievable is what it is. They’re up there till their fingers are bleeding."

The Ten Cent Cinema was originally named "Fifty Cent Cinema". This was most likely a reference to the rapper, 50 Cent.

East of the rock quarry a mysterious underwater hatch can be found, with light shining out of the small window. The hatch itself is very similar to the one seen in the television series Lost and emits a morse code in the form of a banging sound. This code can be translated to "Hey, you never call, how d'you fancy going bowling?", referencing Roman Bellic from Grand Theft Auto IV.

In the international version of the game, Michael tatoos a penis onto Lazlow in the mission "Reuniting the Family". This drawing was replaced with a rocket-ship in the Japanese version. The dialogue was also changed to say "Should I draw a little bit more smoke? Is it about to begin now?".

At one point in development, Amanda had a ponytail in "Did Somebody Say Yoga?".

As seen in the Official Gameplay Video, the statistic bars were originally full bars, not segmented like in the final game.

An early picture of Professor Rashkovsky can be found in the game's files.

An early Rockstar Editor logo can be found in the game's files.

According to files in the game, the Gusenberg Sweeper was named the Gusenberg Chopper during development.

Using the ragdoll physics to hit people sitting down kills them instantly, no matter how minor the collision is.

While listening to FlyLo FM, it's possible to hear Carl, a character from the Adult Swim cartoon Aqua Teen Hunger Force, call in and complain about the music being played.

Originally in "The Long Stretch", Stretch did not wear a hat, Franklin wore his default outfit, and Lamar wore his outfit with the green shirt.

There is a park bench in Pacific Bluffs paying respect to Chris Edwards, a Rockstar Employee who was credited for working on Max Payne, Grand Theft Auto, and L.A. Noire. Mr. Edwards unfortunately passed away in 2014, and this bench is a tribute to him.

Even though Grand Theft Auto has always avoided including children in their games, there is an in-game website in GTA 5 (www.accept-the-chaos.com) which contains a graphic image of dead and mutilated children.

The Jerry Can was originally green instead of red, as seen in pre-release screenshots.

Looking through the game's files suggests there was originally a feature that allowed the player to play music from the characters' phones.

There was originally a "Rubbergun" in the game. It was similar to a Micro SMG, but shot rubber bullets instead.