Shermans of many shapes and sizes

M4A1 (75mm)- 9,527 unit built between Feb 42 to Jul 1945, First variant produced and longest production run. Used Continental R975 Radial engine

 M4A1 (76)W   The upgraded 76mm M1 gun offered enhanced anti-tank power over 75mm gunned version, and had "Wet" ammo stowage improving combat survivability, while better against the Panther and Stug it still lacked when it came to the Tiger

M4A2 - 10,968 built between Apr '42 & July '45 all used GM6046 Twin Diesel Engine (only Sherman to have diesel, favoured by USMC, and used by UK and  Russia. 

M4A3 (75mm) - 12,596 built between July 42 and June 45 with Ford  GAA V8 Gasoline engine, not exported,, most popular, only visible difference to A2's was a wider grill over the engines. Majority of all A3's were converted to E8 76w spec

M4A3-E8 76w only visible difference to A2's was a wider grill over the engines. Majority of all A3's were converted to E8 76w spec, this is the tank "Fury" is based on

M4A4 - Built by Chrysler July 42 - Nov 43 7,499 Built, longer than standard M4 due to large Chrysler Multibank 30 Cylinder engine most being exported (FYI  some converted to  Firefly - see RAC section)