Steering wheel noise should not be overlooked as it can affect or damage other parts or your car.
Many variables can affect the noises or sounds that originate from your automobile's steering wheel. The majority of which can occur when attempting to turn the wheel. The vehicle's make and model is one such factor, as is the particular type of steering system that has been installed. Older cars usually do not have built-in power steering so in these cases you can get rid of possible power steering fluid issues. Cars, vans, trucks or SUV's that are newer are most likely to be equipped with power steering. However, you will need to identify whether the systems is a rack-and-pinion or re-circulating ball steering. The whole steering system interacts with many other parts of your entire suspension system, but most noises emanating specifically from steering manoeuvres can be isolated and diagnosed.
You can begin the diagnostics by shutting off your engine and manually turning the steering wheel. Pay attention to the noise and try to figure out exactly where in the actual turning ratio of the wheel you begin to hear the sound. To be more specific, try to determine whether the sounds start right at the beginning of your turn, at either or both extremes of your turn, or is a nonstop noise throughout the whole turn. Also pay close attention to whether your car needs to be in motion for the sound to occur.
Try to recognize the type of sound you are hearing to the best of your ability. This is important because if you bring it to a professional mechanic they will most likely ask why you this question. Some examples of this could be a while, a clunking, a groaning, a squealing, or a screeching. If you can at least describe this then you have successfully made a preliminary diagnosis.
If you are hearing a whining noise then double check your power steering pump belt. The solution is basically tightening or replacing it if it is the issue. If the sound is happening only at the extreme ends of the wheel turns, and the belt seems okay, then you may not have any potential issues. A screeching sound can plainly indicate you are turning the wheel too hard to a point where it is way past its capabilities.
If a squeal is hard than examine your power steering fluid level. This may indicate that the pump is pumping more air than oil. Please note that fluid reservoir dipsticks have 2 level markers where the first one indicates the cold engine level while the second one is the running hot engine level. On an older automobile there may only be a single mark for warm/hot engine level only. If you notice that the level is quite low and below the first market then buy some more from your local automotive store to fill it up or take it into a service shop. If the fluid level is extremely low then the whining sound will be accompanied by a difficulty in actually turning the wheel with your hands.
When there is a screeching sound take a look at the physical status of the pump itself. A worn out pump can produce exceedingly horrible sounds even with adequate fluid levels. This is when you will need to replace the entire pump.
A clunking noise, while turning your wheel, will require you to investigate your whole suspension system especially if the vehicle is in motion. Another thing to notice is that the sound may also be heard when braking or going over bumps in the road. Vibration may also be felt through the wheel as well. In this case, the possible issues can be plentiful, and may not be fixed with something as simple as pouring in a little bit of fluid to top it off. You will need to thoroughly examine your struts, shocks, and other suspension related parts. This is the most extreme, and dangerous, type of condition and it is highly recommended that you cease driving your vehicle immediately and arrange to have it towed to a professional garage for repairs.
As you can see, there are many types of steering wheel noises and you need to know what each one means. Diagnosing the correct steering wheel noises will greatly help prevent any potential hazardous problems. So if your steering wheel is making noise don't procrastinate and just leave it, diagnose the issue right away and arrange to have it fixed as soon as possible if necessary.