Sherman tanks were numerous and reliable, but poorly armored and vulnerable to the anti-tank weapons they faced.  Crews added layers of spare track, logs, sandbags, and applique armor to weak points but German 75mm and 88mm rounds could penetrate and kill Sherman tanks from any angle at ranges up to 2000 yards.  

With the failure of the T-14 heavy tank concept, the Armor Test Board created a Sherman variant with double the existing armor and a larger, thicker cast turret. The M4A3E2 was heavier and a bit slower, but better suited to the ‘Spearhead Role” in armored and infantry attacks. Only 254 examples were actually produced by the Fisher Body company and 250 were rushed to Europe. 

Initially armed with a 75 mm gun, 3rd army units later up-gunned 100 exampled with the 76 mm M1A1 cannon.  The 75mm cannon was chosen for its more flexible high explosive shell to support infantry attacks.



The tank made its debut in the fall of 1944 and immediately made a difference.  All models had duckbill track for better automotive performance and the differential had a lower gear ratio for for the additional 8 tons of armor weight.  Speed was reduced 2 mph but it was worth the added survivability.  One example of the Jumbo’s durability, a vehicle survived 3 head on shots from and 88 mm gun only to be taken out by a fourth round that penetrated the gunner’s sight aperture.  

Many examples had either .50 cal co axial machine guns or bow mounted flame throwers.      The most famous Jumbo , Cobra King, was recently discovered as a gate guardian at a US army facility in Germany and is undergoing extensive reconstruction at Fort Knox