US M4 Sub-Types
M4- Continental radial engine; welded hull; 75-mm and 105-mm versions only. Users: US, Britain, Poland, France (one vehicle). Some very late M4s had composite cast/welded hulls (cast hull front identical to M4A1 (76) W.).
M4(105) - Upgraded with 105 mm M4 howitzer.
M4(105) HVSS - M4(105) w/ HVSS.
M4A1 - Continental radial engine; one-piece cast hull; 75-mm and 76-mm versions built. Users: US, Britain, South Africa, France (small numbers), China
M4A1E4/M4A1(76)W - Upgraded with 76 mm M1 gun.
M4A1E8/M4A1(76)W HVSS - Upgraded with widetrack Horizontal Volute Spring Suspension (HVSS), fitted with the 76 mm M1 gun.
M4A1E9 - Unknown configuration, possibly an upgrade of existing M4A1s with 76 mm guns.
M4A2 - Diesel-powered; welded hull; 75-mm and 76-mm guns. Users: USSR (M4C), USMC, France, Britain, Poland. No US Army combat use.
M4A2E8/M4A2(76)W HVSS - Upgraded with widetrack Horizontal Volute Spring Suspension (HVSS), fitted with the 76mm M1 gun.
M4A3 - Ford GAA V-8 engine; welded hull; 75-mm, 76-mm, and 105-mm guns. Users: US, France (small numbers). The M4A3 was the preferred US Army vehicle.
M4A3(75) - M4A3 w/ 75mm M3 gun.
M4A3(105) - M4A3 w/ 105mm M4 howitzer.
M4A3E2 Assault Tank - postwar nickname "Jumbo"/"Cobra King" - extra armour (including 4" on front), vertical sided turret, but about 3-4 mph slower. Built with 75 mm gun but frequently re-armed by the using units with 76-mm guns. Grousers fitted to the tracks. Users: US, France (one vehicle)
M4A3E4/M4A3(76)W - M4A3 w/ 76mm M1 gun.
M4A3E8/M4A3(76)W HVSS (Easy Eight) - Upgraded with widetrack Horizontal Volute Spring Suspension (HVSS), fitted with the 76mm M1 gun. The new suspension allowed for more armor to be added.
M4A3E9/M4A3(105) HVSS - Upgraded with widetrack Horizontal Volute Spring Suspension (HVSS), fitted with the 105mm M4 howitzer.
M4A4 - Chrysler A57 engine; welded, lengthened hull; 75-mm gun only as-built. Many re-armed with British 17-pounder guns ("Firefly"). Users: Britain, France, China
M4A5 - No US vehicle was built with this designation; the number was meant to signify Canadian production.
M4A6 - Diesel engine; composite cast/welded hull lengthened similarly to the M4A4; 75-mm gun only. Only a few dozen of this variant were built and none were used in combat.
[edit] US Non-"M4" Sherman-based Vehicles
Variants without the M4 designation but built on the M4 medium chassis (While some began on the M3 chassis, some subvariants were switched to the M4 chassis during production. These are the models listed here):
105mm Howitzer Motor Carriage M7B1 - self-propelled 105 mm Howitzer Motor Carriage (HMC) based on the M4A3 Sherman chassis.
155mm Gun Motor Carriage M12 - self-propelled 155 mm Gun Motor Carriage (GMC).
Cargo Carrier M30 - Cargo Carrier (an M12 with crew and ammunition space in lieu of the gun).
155mm Gun Motor Carriage M40 - self-propelled 155 mm GMC (Either M1A1 or M2 gun) based on the M4A3 (HVSS) chassis.
8in Howitzer Motor Carriage M43 - self-propelled 8 inch HMC (standardized post-WWII).
3in Gun Motor Carriage M10 - tank destroyer based on the M4A2 Sherman chassis.
3in Gun Motor Carriage M10A1 - Same as the M10, but based on the M4A3 Sherman chassis.
90mm Gun Motor Carriage M36 - tank destroyer based on M10A1 hull (M4A3 chassis); standard model.
90mm Gun Motor Carriage M36B1 - tank destroyer based on M4A3 Sherman hull and chassis; expedient model.
90mm Gun Motor Carriage M36B2 - tank destroyer based on M10 hull (M4A2 chassis, diesel); expedient model.
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