The Lee Medium Tank M3 was an American tank used during World War II. In Britain the tank was called by two names based on the turret configuration. Tanks employing US pattern turrets were called the General Lee , named after Confederate General Robert E. Lee. Variants using British pattern turrets were known as General Grant , named after U.S. General Ulysses S. Grant. Design commenced in July of 1940, and the first M3s were operational in late 1941. The M3 was well armed and armored for the period, but due to design flaws (high silhouette, archaic sponson mounting of the main gun, below average off-road performance) it was not satisfactory and was withdrawn from front line duty as soon as the M4 Sherman became available in large numbers.Of the 6,258 M3s produced by the U.S., 2,855 M3s were supplied to the British Army, and about 1,386 to the Soviet Union. One of the American M3 medium tank’s first actions during the war was in 1942, during the North African Campaign. British Lees and Grants were in action against Rommel’s forces at the disastrous Battle of Gazala on May 27th that year. They continued to serve in North Africa until the end of that campaign. A regiment of M3s was also used by the U.S. 1st Armored Division in North Africa. In the North African campaign, the M3 was generally appreciated for its mechanical reliability, good armor and heavy firepower. Created in 1942, this technical manual reveals a great deal about the M3’s design and capabilities. Intended as a manual for those charged with maintenance, it details many aspects of its engine, cooling, transmission and other systems. 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.