In the post-World War 2 period, the newly-established nation of Israel became one of the many beneficiaries of surplus American M4 Sherman Medium Tanks. These fought during the 1948 Israeli War of Independence alongside other World War 2 period pieces and, from this experience, the Sherman was consistently modified / modernized to satisfy growing Israeli Army requirements. In time, the series had run its course once again and was due for, yet another, modernization.
After inspecting, first-hand, the new French AMX-13 Light Tank in 1953, the Israelis selected the gun of this vehicle - the 75mm CN 75-50 - to be installed on the existing hull of the M4 Sherman which remained the standard Israeli Army tank for the interim. With French help, the modification was made and a pilot vehicle was formed in 1956. After the requisite trials, serial production of this "Super Sherman" ensued and the vehicles were designated as Sherman "M-50" - known locally (and unofficially) as the "Isherman".
The initial 50 vehicles were built atop the chassis and hull of the M4A4 Sherman production model complete with their original VVSS suspension systems and Continental R-975 gasoline-fueled engines. After these tanks were shown to be overweight, straining their engines, the rest of the line shifted to the wide-track HVSS suspension system and the less-flammable Cummins V-8 diesel engines of 460 horsepower output. By 1964, some 300 total M-50 tanks has been produced.
Another offshoot of this Sherman line became the M-51 "Isherman" which followed the same basic concept - though the French-originated 105mm Modele F1 was used instead (which considerably broadened the Sherman's firepower). The Sherman M4A1 production model was used with the Cummins diesel engine / HVSS suspension system combination from the outset. Introduction of the M-51 arrived in 1965.
The M-50 tank debuted in October of 1956 against Egyptian forces in Sinai. The vehicle gave a good showing and then later joined the M-51 series in the Six Day War of 1967 and the Yom Kippur War of 1973. Despite its World War 2 roots, the design soldiered on even against more modern armor like Soviet T-54/55 Main Battle Tanks and up-gunned T-34 Medium Tanks. The line was in operational use into the 1980s.
Some of the used Israeli stock was sold off to the Chilean Army and the remaining tanks in the Israeli Army inventory ended their days in second-line roles, typically stripped of their armament and turrets.