When you turn the steering wheel, the two front wheels also turn in the desired direction. In reality, many different components are needed to translate the rotational movement of the steering wheel into a side-to-side movement for the front wheels. Your steering wheel connects to the steering column, which connects to an intermediate shaft, which connects to the steering rack / gearbox. The frame itself is what moves the wheels to the left or right, allowing you to drive.
The steering rack / gearbox is also responsible for providing the electrical assistance that makes driving your car easier. Today’s vehicles are quite heavy and manual steering is difficult even under the best of circumstances. Your rack is connected to the power steering pump, which pushes fluid through the lines and onto the rack, increasing and amplifying the movement created by the steering wheel.
Your car’s rack / gearbox is used every time you turn the steering wheel. You are also subject to a lot of stress and vibrations even when you are not turning (driving on a straight section of the road). Eventually the shelf will fail. However, there is no definitive shelf life here. The more you drive, the faster it will wear out. Still, most vehicle owners will never have to change their power steering rack, or need to replace it only once during their ownership.
Given the immense importance of the steering rack / gearbox, it is vital that you are aware of some signs and symptoms of excessive wear to watch out for. These include the following:
- The steering wheel feels loose or sloppy
- You see power steering fluid leaks under the car, behind the engine
- You hear a metallic noise when driving over potholes or turning the steering wheel
- Steering wheel feels “disconnected” (many turns required)
- The direction is uneven
- It takes a lot of effort to turn the wheel
If you have any of these problems, it is very important that you have your gearbox / steering rack inspected. A professional mechanic can inspect the system and replace the steering rack / gearbox, as well as any other faulty components.