A more radical upgrade with longer chassis with 6 road wheels each side, a 690 hp V-46-5M diesel engine and with the complete turret with automatic loader and 2A46M 125mm main gun of the T-72B. Also the protection was increased to T-80U level. Optionally the tank can be equipped with the 1A40-1 fire control system with ATGM system 9K120 "Svir" (as T-72B) or with the 1A42 and 9K119 "Refleks" systems (as T-80U). Combat weight is 43 tonnes.
Taiwan's M41D life extension system upgrade includes a new, locally produced 76mm main gun, new diesel engine, thermal targeting system, digital ballistics computer and laser rangefinder, and reactive armor. However, the tank lacks stabilized sights and cannot fire on the move, and is relegated to scouting and counter-amphibious operations.
What are your favorite old upgraded weapons?