When you look at the shirt on your gang members, they have a number 7 on the back, and Rimmers written on the front. The design on the shirt is actually of the Saints. You can actually get a Saints shirt at the ProLaps and see the same design
On any Burger Shot menu sign, it shows one of the items for sale is Freedom Fries. This short-lived renaming of French Fries didn't occur until the Iraq war, along with France's refusal to help America in the subsequent operation Iraqi Freedom.
The sign on Mr Grant's bike shop in Dillimore shows a freeride mountain biker, a style of mountain biking that didn't reach prominence until the late 1990s. Furthermore, the bike that is on the sign is a Specialized Big Hit - a model that didn't come out until 2003.
When listening to the first episode of "I Say, You Say", a caller says he shoots in his yard that he doesn't recognize. Then he says he has 15 illegal immigrants in his yard, and he killed them with his hands.
In the mission, "Drive-Thru," Big Smoke is sitting directly behind CJ, and Sweet is opposite him in the cut scene when they are ordering the food. Later, when they reach Grove Street, Sweet and Smoke have switched seats.
If you get in a train in Los Santos and derail it near North Rock (the easiest place to do it) you will only find two train cars, yet there were three on the train: The locomotive, and two passenger cars.
There are three types of license plates in the state: San Fierro, Los Santos and Las Venturas. When you go to Mt. Chiliad, there is a Camper van. If you read its license plate, the words and numbers are backwards, facing inside the car.
When Cesar is talking to CJ in the cut-scene for the mission "Cesar Vialpando", the cars and persons of the recent low-rider event are gone. However, after the cut-scene you see the previously gone cars and persons go away.
In the cut-scene for the mission "High Stakes, Low-Rider", you see Kendl sitting next to Cesar on the passenger seat. However, after the cut-scene, Kendl is gone and another girl is sitting in place of her.
When going into the 24-7 at Little Mexico, across from the Unity Station, go to the right and look at the first arcade game. It says "Go Go Space Monkey". Play the game and it shows the game "They Came from Uranus".
When you are using a Tec9\Micro SMG\SMG, the ammo is the same for all of them, meaning that if you use a Tec9 and walk over an Micro SMG, you will get some ammo. But when you are using a 9mm handgun, you cannot get any ammo by walking over a silenced 9mm, and vice versa.
The cash register displays of all fast food restaurants show two products: the Buster and the Double D-Luxe. The register calculates a price of 20 dollars in total. But the Buster costs actually two, the Double D-Luxe five dollars. The calculation is wrong.
Before the mission "End of the line" sometimes you can see the
hole in the wall you crash through with the SWAT tank to get to the crack palace. You can also see the part of the Sprunk billboard sign that will become a hole at the end of the "Reuniting the families" mission.
The goof item below may give away important plot points.
In the 'End of the Line' mission, there is a cut scene where
CJ and Big Smoke meet in Big Smoke's crack fortress. When CJ and Smoke are ready to fight, Smoke takes a SPAS combat shotgun. When the cut scene ends and you have to kill Smoke, he has an AK-47 instead.