The vehicle's early design work was based on General Dynamics' M1 Abrams, with some noticeable differences including a combined system of hydropneumatic suspension and torsion bars, and a river-crossing fording kit, to meet the required operational capability that was specific to combat operations in the mountainous and swampy terrain of the Korean Peninsula.
It was deemed that, even if the M60A1s were obtainable, there would not be enough of them to give the South Korean forces a significant advantage over existing North Korean tanks.The XK1 retained the XM1's M68E1 105 mm rifled main gun, which would also be domestically produced under license with the designation KM68, as well as a fire control system by Hughes Aircraft Company and the Nd: YAG laser rangefinder.However, upon closer inspection, numerous differences can be found.The differences included the weight (55-ton XM1 versus 51-ton XK1), height (2.37 m versus 2.25 m), engine (1,500 hp Honeywell AGT1500C for XM1 versus 1,200 hp Teledyne Continental AVCR-1790, also used on Merkava 3, for XK1, although the XK1's engine will later be replaced with MTU MB Ka-501, a compact version of the 1,500 hp MB-873 Ka-503 used on Leopard 2), transmission (Allison DDA X-1100-3B for XM1 versus ZF LSG 3000 for XK1), and several other components used in the vehicles.
A number of other plans were also devised, such as upgrading the existing M48 Pattons to the M48A3 and A5 standard, as well as obtaining the license to domestically produce Germany's Leopard 1 main battle tank. In light of this, the Park Chung-hee administration announced plans to domestically produce main battle tanks that were comparable to the newer generation of main battle tanks.
Only the upgrades to the Pattons were carried out, with the results being the M48A3K and M48A5K, while producing Leopard 1s was deemed counterproductive, as a newer generation of main battle tanks were already being developed and tested in both the U. However, having absolutely no experience in the design, development and manufacture of main battle tanks to speak of, the task assigned to the South Korean industry was all but impossible.