The steering gear may be mechanical, hydraulic, pneumatic, electric or a combination of any of these. In the case of trailers, "steering gear" means all the components which transmit to the steered wheels the force necessary in order to obtain a change in the direction of movement of the vehicle., the two geared members attached to the steering column and the drop-arm spindle respectively. They transmit motion from the steering-wheel to the stub axles through the drop arm, steering rod or drag link, steering arms and track rod., hammasmehhanism, mis muudab rooli pööramise edasi-tagasi liikumiseks