The M48 Patton is an American medium tank and the third and final tank to be named after Gen. George S. Patton. Patton, commander of the U.S. Third Army during World War II, was one of the earliest American proponents of tanks. The M48 was a further development of the M47, and served as the U.S. Army and Marine Corps's primary tank during the Vietnam War. The M48 was a completely new tank design, and the last U.S. tank to mount a 90mm gun. Nearly 12,000 were built between 1952 and 1959. It was initially outfitted with a somewhat unreliable gasoline engine which, during the Arab-Israeli conflicts, proved vulnerable to conflagrations when hit by enemy fire. Beginning in 1948, some units were upgraded to the M28A3 model which used a safer and more reliable diesel engine. In the mid-1970s improved M48A5 models were created which carried the 105mm gun. These served well into the 1980s with American forces and many continue in service today with foreign armies. Created in 1955, this field manual reveals a great deal about the M48's design and capabilities. Intended as a manual for training and operation, it details many characteristics of the tank, and explains in detail the fire-control instruments. Furthermore, it describes the firing duties, crew drills, and service of the piece. Originally labeled restricted, this manual was declassified long ago and is here reprinted in book form. Care has been taken to preserve the integrity of the text."