For the Allied tankers and infantrymen of the American, British, Canadian, and Free French armies battling German Panther and Tiger tanks in Normandy in the summer of 1944, the Sherman tank’s failures were glaringly evident as their own shells bounced off the hulls of the Nazi armor and they were themselves destroyed at a far greater range by the powerful German tanks.
It was, therefore, somewhat ironic that the outgunned and lighter armored Shermans nevertheless defeated the retreating Nazis by their sheer weight of numbers. Today, more than seven decades after the end of the greatest war in military history, the debate continues. Was the American-designed and -built Sherman M4 medium tank a colossal blunder, a wonder weapon, or both?
Author Philip Trewhitt wrote, “The Medium Tank M4 Sherman used the same basic hull and suspension as the M3, but mounted the main armament on the gun turret rather than the hull. Easy to build and an excellent fighting platform, it proved to be a war-winner for the Allies. By the time production ceased in 1945, more than 40,000 had been built. There were many variants, including engineers tanks, assault tanks, rocket launchers, recovery vehicles, and mine-clearers. The British employed the Sherman extensively, notably at the Battle of El Alamein in 1942. Though outgunned by German tanks and with insufficient armor to compete in the later stages of the war, the sheer numbers produced overwhelmed enemy armored forces. Its hardiness kept it in service with some South American countries until very recently.”
The Evolving M4 Sherman Series
With a crew of five, the Sherman weighed over 66,000 pounds, was 19 feet, four inches long, eight feet, seven inches wide, and nine feet high. It had a range of 100 miles, armor of .59-2.99 inches thick, and a single 75mm turret gun, plus one coaxial 7.52mm machine gun and a .50 caliber machine gun on the turret. The power plant consisted of twin General Motors 6-71 diesel engines that developed 500 horsepower. Its maximum road speed was 30 miles per hour, and it could ford a stream three feet deep, mount a vertical obstacle two feet high, or cross a trench seven feet, five inches wide.
The M4 series entered service in 1941, and was built by American automobile manufacturers Chrysler, Ford, and General Motors. Both hulls and turrets were either welded or cast. The five-speed transmission was a synchromesh with front sprocket drive and a controlled differential, while the vertical volute suspension was changed to horizontal on later models, and its fuel capacity was between 140-175 gallons.
The most refined Sherman model was the M4A3. It differed from the M4A2 primarily in turret and suspension, utilizing the horizontal volute spring system, while its armament was the more effective high-velocity 76mm gun and its armor was thicker in vulnerable areas.
Ford built the M4A3 between June 1942 and September 1943, and later Grand Blanc produced the variant. Other improvements were a vision cupola for the commander, wet ammunition storage, and a loader’s hatch.
The M4A3 Sherman medium tank also had a five-man crew, a weight of 71,024 pounds, and a range of 100 miles. Its length with gun was 24 feet, eight inches, and the hull length was 20 feet, seven inches. Its width was eight feet, nine inches, and its height was 11 feet, 2.85 inches. Its armor plating was up to 3.94 inches, and a single 7.62mm coaxial machine gun complemented the 76mm main weapon. The powerplant consisted of a Ford GAA V8 gasoline engine developing 400-500 horsepower. Its maximum road speed was 30 miles per hour, and its fording ability was three feet. It could surmount a vertical obstacle two feet high and a trench 7 feet, five inches wide.
40,000 Shermans vs 6,635 Panzers
Against those 40,000 Allied Shermans, the Nazis fielded but 1,835 Tiger and King Tiger tanks and 4,800 Panther tanks, for a grand total of 6,635. Some estimates of Sherman wartime production reach an astounding 50,000.
Ironically, the United States entered World War II without an armored fighting vehicle such as the Sherman available. Thus, its new design was developed too quickly and the normal, slow-moving series of developmental stages was cast aside in favor of getting the M4 into immediate mass production. The Allies paid for this hasty decision later on in the summer of 1944 in the fields and hedgerow country of embattled Normandy against far superior German armor.
The enormous production numbers also resulted from this initial strategic decision to produce Shermans in large quantities rather than wait for a heavier armored vehicle, such as the M26 Pershing heavy tank, which finally arrived just before war’s end in 1945.
On the pro side of the ledger, the M4 Sherman was technically uncomplicated, reliable, and mechanically well constructed. It also helped that the Allied air forces enjoyed a huge aerial superiority over the virtually beaten German Luftwaffe. Working in tandem with well-coordinated Allied infantry, artillery, and air forces, the plentiful and trusty Shermans were able to vanquish most German armored formations simply by ganging up on them in overwhelming numbers when all else failed.
On the con side, however, the Sherman’s 75mm and 76mm guns just could not pierce the mighty Tiger tank’s frontal armor even at short range while the latter could vanquish the Shermans with impunity from greater distances. Another drawback was that, unlike the German tanks and the Soviet-built T-34 medium tank, the Sherman made a far more visible target in combat because of its height.
In addition, noted one source, “In fact, to destroy a German Tiger, the Shermans had to hit it from the side or from behind, and obviously if the Tiger saw them approaching, it could destroy some Shermans before the others could eventually destroy it.” That was, alas, too often the case.
Powerplants for U.S. tank production were always a major problem, and eventually this led to the development of the 8-cylinder Ford-produced engine. Although originally designed for aircraft, the Ford 8 cylinder was gasoline fueled and had 500 gross horsepower. Following testing, the engine was authorized by January 1942 for Sherman usage by the U.S. Army Ordnance Committee, and with the new engine, the first M4A3 was completed by May 1942.
Testing was completed at the General Motors Proving Ground, with minor changes being made. By September 1943, fully 1,600 tanks had been constructed when Ford ceased production. This was taken over by the Detroit Tank Arsenal and also the Fisher Tank Arsenal, and by mid-1943 there were already numerous other changes.
Stated one account, “Distinguishing turret features included an all around vision cupola for the commander—except in early production, which retained the earlier circular split ring hatch—and an oval shaped loader’s hatch. Those vehicles produced with the circular split ring commander’s hatch had it replaced by the all around vision cupola in the field as supplies became available.”
The Widely Used M4 Sherman
The Canadian Army replaced its Ram tank with the versatile Sherman model for the invasion of Italy in July 1943. Sherman tanks were also produced in Canada under license agreement.
Named after the American Union Army General William Tecumseh Sherman, the M4 medium tank was used not only in World War II, but also in the Greek Civil War, the Arab-Israeli War of 1948, the Korean War, the Suez Crisis of 1956, the Indo-Pakistani War of 1965, the Arab-Israeli War of 1967, the Indo-Pakistani War of 1971, and the 1973 Arab-Israeli War.
The M4 Sherman’s Debut
The original M4 was debuted on August 31, 1940, with final characteristics completed on April 18, 1941 at the Aberdeen Proving Ground. The first pilot M4 was finished on September 2, 1941, and then put into mass production during February 1942. Altogether, there were seven models: M4, M4A1, M4A2, M4A3, M4A4, M4A5, and M4A6.
Stated one account, “The sub types differed mainly in terms of engine, although the M4A1 differed from the M4 by its fully cast hull rather than by engine; the M4A4 had a longer engine system that also required a longer hull, longer suspension system, and more track blocks. The M4A5 was an administrative placeholder for Canadian production, and the M4A6 also elongated the chassis but totaled fewer than 100 tanks. Only the M4A2 and M4A6 were diesel; most Shermans were gasoline fueled.”