The first American Lend Lease tanks arrived in the USSR towards the very end of December 1941. The volume of shipments was small at first, but this changed in the spring of 1942. American light and medium tanks began arriving in large amounts and were widely used in battle by that summer. The Medium Tank M3, known as the M3S or M3sr, was the most common American medium tank shipped in 1942, but towards the summer the Americans began to shift production to the more successful Medium Tank M4. Its diesel variant, the Medium Tank M4A2, became the most common foreign tank used by the Red Army.
A complicated American
The diesel powered Medium Tank M4 came about due to the vastly increased demand for medium tanks. They were built not only for the Americans, but also for the British. The American diesel tank was largely meant for the British. They initially wanted to produce the Matilda tank at American factories, but the Americans refused this proposal after examining the tank. A decision followed to produce special variants of American tanks for the British.
The most famous such tank was the Grant I, created in part by L. Carr, a tank specialist from the Department of Mechanization. He was also the father of the American tank diesel engine. The GM 6-71 2-stroke water cooled 6.98 L engine was chosen as the optimal candidate. This engine was used on buses initially, but during the war its applications became broader. A pair of these engines indexes GMC 6046 was used first on the Medium Tank M3A3 and M3A5. These tanks never saw battle, but the fate of the next diesel tank, the Medium Tank M4A2, was different. The Fisher Tank Arsenal delivered the first vehicles of this type in April of 1942. Due to a high level of parts commonality changes to the chassis were minimal. The biggest changes had to do with the rear hull plate and engine deck. Five different factories produced the M4A2. 8053 tanks of this type were produced until May of 1944, of which 4616 (more than half) were built at Fisher.