- Grand Theft Auto III
- Grand Theft Auto: Vice City
- Grand Theft Auto: San Andreas
- Grand Theft Auto Advance
- Grand Theft Auto: Liberty City Stories
- Grand Theft Auto: Vice City Stories
The truck is absent in Grand Theft Auto IV as the military has been removed from the game.
Appearing on the streets only when the player achieves a 6-star wanted level, the Barracks OL is a military truck based on the M939 "5 ton" truck. When first introduced in GTA III, it was visually very similar to the the Flatbed truck, differing only in its body colors and its modified bed design with additional fencing. Unlike the Flatbed, the Barracks OL underwent fewer modifications after GTA III, retaining its rugged, military-like design.
The Barracks OL comes with three types of bed configurations: uncovered, uncovered with framing, and fully covered; GTA San Andreas' Barracks, however, features only two bed configurations: covered with tarpaulin, or covered with camouflage netting (revealing boxes on the bed). The GTA San Andreas and GTA Advance renditions feature closed cabs, while all other renditions feature open cabs. Despite the Barracks' huge size, it is only capable of carrying the driver and one passenger.
From GTA Vice City onwards, Vigilante missions can be activated from the Barracks OL. In GTA San Andreas, the Barracks even features a siren without strobe lights, which, like other sirens, will force traffic in front of the truck to move out of the way.
Although it is one of the heaviest vehicles in the games, it is faster than the much lighter Flatbed; due to its length and its two rear axles, however, it suffers from understeer at higher speeds. Its ramming power is impressive; it can easily penetrate a SWAT roadblock. The Barracks OL has all-wheel drive, but, because of its size and weight, it can easily get stuck in off-road terrain. Despite its size, the Barracks will explode if it collides with a Rhino tank, just as other vehicles do. The Barracks OL has an average top speed but the acceleration leaves much to be desired.
- Boxes found on partially covered Barracks in GTA San Andreas appear to be labeled as containing ammunition, but are further labeled humorously with warnings not to eat the boxes' contents ("Do Not Eat!").
- In GTA Vice City Stories, a bulletproof Barracks OL will appear in the mission Truck Stop. It's difficult to obtain and the truck won't be bulletproof anymore once Phil Cassidy has taken control of the truck, due to the health bar.
- There is a glitch on the Barracks with the camouflage netting in the PS2 version of GTA San Andreas, which is, if you press the select button to change the view, change it to the bumper view and hold the L2 & R2 buttons to look back, the netting will disappear and the only thing you will see is the bed of the truck. And if you press the button again to the full truck view the netting will return.
- The Barracks OL rendition of GTA LCS cannot be used for Vigilante Missions, despite it's being used by the Army. Also, the Barracks OL has a radio, which is the only kind in GTA LCS.
- In GTA 3, a bulletproof Barracks OL appears on the mission Arms Shortage. It is difficult to obtain because there are on other things to block off the fire from the cartel, and is normal once the mission is over. However, you can park it in front of Phil and attempt to push the Rhino to your garage.
- The Barracks OL is the first vehicle seen in GTA Vice City Stories, it appears in the first game cutscene when it's shown Vic entering in Fort Baxter with it therefore also being the first chronologically seen in the 3D Universe.
- In GTA VCS during a mission Skywolf, you use a Hunter to fly through checkpoints and shoot drones, but the drones are Barracks OL's, but with a different design then the normal ones you see in Fort Baxter. Also, if you try to get in one, the doors are locked, making it an interesting mystery. Perhaps these were beta vehicles.
- Phil's Army Surplus, in north Rockford, Staunton Island Bulletproof version during the mission Arms Shortage.
GTA Vice City
GTA San Andreas
- Area 69, Bone County
- Easter Basin Naval Station, San Fierro
- Once the player reaches a 6-star wanted level, replacing FBI Ranchers, road blocks will consist of these, along with tanks pursuing the player.