Work on a replacement for the M47 began in December 1951. This new design retained the same engine and transmission as the M47 but was otherwise a completely new design with new turret and hull. Like the M47, over-hasty schedule without adequate testing resulted in the first batch of M48 coming off the production line in April 1953 with serious technical problems. The M48 was distinguishable y its distintive round turret. ABout 3,200 M48 were built.
Variants:
M48A1 - Identical to M48 except for a completely enclosed cupola housing the ,50-cal machine gun previously exposed.
M48A2 - This version addressed the M48A1's greatest tactical deficiency with its short range of only 112km with a new fuel injection engine and a larger fuel tank beneath a new rear engine deck which also reduced its infra-red signature. The M48A2 became the standard US medium tank of the late 50s and 60s. Nearly 12,000 were built by the time production ceased in 1959.
M48A2C - Improved fire control system and the deletion of a small return roller between the last road wheel and the drive sprocket.
M48A3 - Rebuilt M48A1s with improvement from the M60 programme and the new engine deck and improved fire controls of the M48A2C. A host of other minor improvements resulted in the M48A3 (Late Model).
M48A4 - Originally intended to refer to M48A3s with M60 105mm gun turrets released by the M60A2 programme, delay to this programme due to this beiing cancelled but the designation was used for administrative purpose to refer to the Israeli-modernised M48A2s with improved engine and 105mm gun provided by the US.
M48A5 - Until production of the new M60 has ramped up sufficiently, it was decided to upgrade all mothballed M48s, M48A1s etc. to M60 standard by a variety of packages. These upgraded tanks were designated M48A5s.
M88 - Armoured recovery vehicle version of the Patton.
XM246 - Entering service in the mid-80s, essentially a M48A5 with a new turret mounting twin 40mm Bofor cannons and a fire control radar for anti-aircraft defense.

Design began in 1956 when the arrival of the Soviet T54 prompted the requirement for a heavier main gun from the standard 90mm medium tank main gun of the time. Again because of the pressure to react to the new threat and the fact that the M48 series is so well established, it was decided to upgun the M48 from 90mm to the new British-designed L7 105mmb and designated this new tank the M60 Patton. The M60 Patton also contain a whole series of improvements from the automotive system to the fire control system.
Variants:
M60A1 - New version featuring a new larger turret allowing more ammunition to be stowed. A new more powerful engine was added to handle the additioanl weight. The M60A1 also introduced a gun stabilisation system which enable the main gun to stay in the general direction of the target no matter which direction the tank was travelling in. Infra-red night sights were also added which necessitate the addition of a large Xenon serchlight above the main gun. Nearly 8,000 M60A1 were produced by the end of 1981.
M60A2 - Attempt to marry the Shillelagh 152mm gun/missile launcher system to the proven M60 hull to produce a lighter, more easily transportable vehicle, to counter the threat of improved Soviet armour in Europe. Resulted in a completely new long narrow turret on esentially the same hull. The plan was to upgrade all M60A1 to this new system but the new gun never lived up to the expectations of the planner and and only 526 units were built between 1973 and 1975. It was completed withdrawn from service in 1980. The 60A2 turrets being removed and scrapped and replaced with the M60A1 version.
M60A3 - Latest version of the M60 with improvement to all areas that will provide a capable main battle tank well into the 21st Century. New equipment includes aaser range-finder, a computerised fire control system together with thermal imaging aiming and tracking system, improved weapon stabilising system, a cross-wind sensor and a thermal sleeve for the main 105mm gun. All M60s are being replaced with M1s in the US inventory but still serves with many armies all over the world.
M728 - Combat Engineer Vehicle.
G2 - Armoured Vehicle Launched Bridge.