Which component is primarily responsible for steering a vehicle?

The steering gear assembly is the primary component that enables a driver to control the direction in which the vehicle travels. It translates the rotational motion of the steering wheel into lateral movement of the vehicle's wheels. This assembly typically consists of several parts, including a steering rack and pinion or a recirculating ball mechanism, which work together to provide precise steering control. When the driver turns the steering wheel, the steering gear assembly adjusts the angle of the wheels, allowing for smooth and responsive navigation of the vehicle.

The other components mentioned serve different functions: the brake system is essential for slowing down or stopping the vehicle; the suspension system supports the vehicle's weight and absorbs shocks from the road, contributing to passenger comfort and handling; and the exhaust system manages the emissions produced by the engine, directing fumes away from the vehicle. Each of these systems plays a vital role in the overall operation of the vehicle, but none are responsible for steering it directly.