The gun truck named 'Pandemonium' was built in late September 1969, by the 88th US Transportation Corps. It was based on a 5 ton M54 cargo truck chassis, originally armed with a rear mounted 7.62 NATO calibre M134 minigun and 2 M2 50. calibre heavy machineguns and heavily armoured with metal plates. According to Robert (Bob) Long of the 88th Transport Unit, driver of Gun Trucks "Lil" Nancy and "Puff The Tragic Wagon" and gunner on Pandemonium he came up with the name.

 

The naming  of this truck actually came from a dream I had. One night, after a few beers, we were trying to come up with a name for our new 5 ton we were building. We came up with a few names but none that all could agree with. I fell asleep (passed out) and had this weird dream about demons, devils, ghosts and goblins all running around slashing, gashing, smashing and goring hundreds of people and leaving piles of bodies lying everywhere. Buildings were riddled with bullet holes and many were blown up and everything was burning. In the background I could here this radio broadcaster describing the scene and referring that all pandemonium and h — had broken out. Weird huh? No dream – it was a nightmare! But a name had been born. Told one of the guys about it in the morning and he agreed that Pandemonium would be a good name for our truck. It took the other guys a bit longer to come around to the name but once I explained my “dream” to them they agreed on the name. (1)

 

At some point during 1970 the rear minigun was replaced by another one or two M2 50. cal's (sometimes seen on a dual mount on other Gun Trucks that used them, for four guns total), and the driver cab was up-armoured with extra roof plating. I am unsure if once the armament changed they added a M79 grenade launcher soldier to the vehicle for even more firepower, but that was relatively common among gun trucks. Because of the amount of firepower the Gun Trucks were putting out, some of the crews of gun trucks tried to deal with that as well- for example, there is a photo of the minigun operator on 'The Untouchable' wearing a radio headset, then a headwrap, then a normal helmet.

 

 

 

 

 

 

 

 

 

While earlier gun trucks, including the 2 tons, had used M60's, but the time the Pandemonium was built the M2 was preferred as a weapon- the minigun it was equipped with was a rather scarce weapon, and was removed in 1970 when the gunner trained in using one left Vietnam. The reason for the preference of the M134 and 50. cal over the M60's on gun trucks was because of how they were employed- they were used for pounding treelines and supressing, and the 50. cal was much more effective at cutting though trees and other foliage, while the M134 was simply hurling an obscene rate of fire, and the ambushes the gun trucks were fighting in were often very close range, 100 to 500 meters, so the M2 was never really used at longer range. The M134 has a selectable rate of fire, but when used on the Pandemonium was not used on the 4000 rounds per minute (RPM) setting, at that went through the limited ammo supply too quickly, so it was used on the 2000 RPM setting, and often with large tracer belts for improved suppression.

Other changed to gun trucks include additional fuel tanks, as well as some being outfitted with towing winches, but Pandemonium was not one of these. All the convoys usually had a logistical/ towing/winch vehicle attached to them, so individual towing winches were not necessary. From 1969 onwards the gun trucks also had their driver compartment outfitted with bullet resistant glass- while very early gun trucks had removed the glass altogether, the concussion from firing the gun over the drivers head was an issue, so glass or extra armour plating, sometimes double-spaced, was added back on.

Some gun trucks, like the 'Eve Of Destruction' had their floor of the vehicle paved with ammunition cans for the 50. cal weapons used by it, and infantry weapons such as M14's, M16's and M60's, as well as the aforementioned M79's, were often stored in the tray for use against targets too close to depress the main weapons, or for assistants to be used while the main guns did not need reloading.

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