I am not an expert on mechanics. Just speak on behalf on my limited knowledge on transmission and steering.
The steering mechanics of the tank is very different from the car. For a car, steering is completely separate from the transmission thing. However,a tank steers by varying the speeding of one of its two tracks. The steering and transmissions are usually coupled. Russian Tanks (T72, T90, probably T14) use the mechanical transmission which has two planetary gearboxs to adjust the speed of two tracks. This type of steering is primitive and unergonomic. The driver steers the tank by applying the two levels that control the motion of the tracks the same way the people drive the tractors. The turning radius is fixed based on the driving speed because of the planetary gearbox design. Inexperienced drivers of russian tanks flip over the tanks frequently due to slight misoperation. The Chinese tanks are not fundamentally different (Type 96 and Type 99)
Germans first introduced the hydro-mechanical transmissions HSWL 354 on their leopard II, which comes with a torque converter like modern car. Its based on fancy electro-hydraulics that allows better control of torque output on the tracks, resulting in much more superior maneuverability, stability, traction control, and efficiency. This design became the benchmark of modern western tanks. Not until recently, we are able some of our new export tanks (VT-4) are equipped with this transmission. Many spectate that 96B is also using tthis powertrain given the same exhaust grille and engine layout. Hopefully its true.