The M274, known as the “Mechanical Mule”, was developed out of the requirement for an infantry ammunition, light cargo, personnel, and weapons carrier. The A-1 had a four cylinder air cooled gasoline engine, while the A2, A3, A4 and A-5 had a 2 cylinder air-cooled gasoline engine. All models were basically the same shape, although materials differed between versions. The A-4 model platform was made of a magnesium alloy while the later A-5 version was made of aluminum. All models through the A-4 have 4-wheel drive and 4-wheel steering. The A-5 has 4-wheel drive and 2-wheel steering. Only the A-5 has electronic ignition as standard. All models are equipped with a 2-speed gear transfer box and a 3-speed forward and 1-speed reverse transmission.
These vehicles will operate over all types of road, cross-country terrain, and in all types of weather. They are also capable of fording 18 inches of water.
Three of these vehicles, apparently discarded, were discovered by Chapman Holbrook behind one of the buildings on the base. He saw that by using parts from three he would possibly be able to restore one to full operating condition. Then, with the help of some of the crew he began the restoration process in May 2001 and finished in July 2004. The vehicle fully operational and parade ready.
