In the steering mechanism there is a rotary valve of control directing liquid from the pump of the hydraulic booster of steering to one or other party of the piston of a gear lath of the steering mechanism. The piston and a gear lath make one integral part of the steering mechanism. The piston of a gear lath transforms liquid pressure to the linear force which moves a lath on the left or to the right.

This force is transmitted through steering drafts and tips of steering drafts on rotary fists which turn forward wheels. At malfunction of the hydraulic booster driving is exercised in the usual mode. However at the same time it is necessary to make bigger effort. Rotary motion of a steering wheel is transferred to a gear wheel. At rotation of a gear wheel teeths of a gear wheel are hooked with lath teeths, thereby force a lath to move.