1. Power steering pump: The power steering pump provides hydraulic pressure to the steering system, allowing you to turn the wheels smoothly. If the power steering pump is low on fluid or has a failing internal component, it can produce a grinding noise when the vehicle is started and turned.
2. Power steering belt: The power steering belt connects the power steering pump to the engine, driving it to generate hydraulic pressure. A loose, worn, or damaged power steering belt can slip and produce a grinding noise.
3. Steering rack: The steering rack is a mechanical component that connects the steering wheel to the wheels. If the steering rack is damaged or has worn out components, it can produce a grinding noise when the steering wheel is turned.
4. Ball joints: The ball joints are spherical bearings that allow the wheels to move up and down. Worn or damaged ball joints can produce a grinding noise when the suspension is compressed, such as when the wheels are turned.
5. Wheel bearings: The wheel bearings are located inside the wheel hubs and allow the wheels to rotate smoothly. Worn or damaged wheel bearings can produce a grinding noise when the wheels are turned.
Note: If the grinding noise is accompanied by other symptoms, such as difficulty steering or a loss of power steering assist, it is important to have the vehicle inspected by a qualified mechanic to determine the exact cause of the problem.
