I am hearing a grinding noise when i turn the wheels?

Assume the noise is coming from under the hood. If the noise only occurs at the far extreme turning point in both directions, this is normal as it is straining the power steering system. If the noise occurs all the time, check the level of fluid in the power steering reservoir. If low, probably a leaking hose or reservoir. Add power steering fluid to get level between min and max lines. Should make sound go away. If the noise does not go away and a flush of the system does not correct it, you may need a new power steering system, although this is pretty rare unless a leak has gone on for a long time with little or no fluid.
If noise is inside the car, one of the parts of the steering column or steering wheel may be bad.

hi Eva.
As you turn your steering wheel it is this fluid pressure that aids in turning the wheels of your car. ... If the pump impeller is trying to move power steering fluid and starts catching air bubbles it can cause whining noises and vibrations to occur.
Maybe you've heard it at a stop light. Maybe you've heard it as you pass a car on the freeway. Or maybe you've heard it in the parking lot at work when someone is leaving. The unmistakable whine of a power steering pump can make even the most confident mechanic wonder when that car will breakdown.
Power steering pump noise is a unique noise that your car may make and once you've heard it you always know what it is. The noise is a mix of a whirring and a whining and will always vary with the speed of your engine whether your car is driving or in park. This whining noise can be subtle or extremely loud and may be worse in colder weather, or right when you first start your car.
Power steering pumps are most often vain style centrifugal pumps that are tasked with pressurizing the power steering fluid and pushing it down to your power steering gear or rack. As you turn your steering wheel it is this fluid pressure that aids in turning the wheels of your car.
There are a few reasons why you are hearing power steering pump noise from your car. First, it may simply be due to the design of the pump. Sometimes, noisy power steering pumps can continue to work flawlessly for years after they start making noise. This may simply be due to the manufacture's design or a tight tolerance in that particular pump. In this case, you would hear the noise but not see any other adverse effect like a loss in power steering, leaking fluid or a wobbly pulley. In this case, you may be able to help reduce your power steering pump noise by choosing a different type of power steering fluid, like a synthetic fluid.
Your power steering pump may also be making noises due to air trapped in the system. If the pump impeller is trying to move power steering fluid and starts catching air bubbles it can cause whining noises and vibrations to occur. Even tiny air bubbles you cannot see that are trapping in the power steering fluid may be causing the whining you are hearing. In this case, the best thing to do is flush your power steering system to try and remove the air from the system. Having air trapped in your power steering system can be difficult to diagnose so you may need to simply try a power steering flush to see if it solves your problem.
Power Steering pump noise may also be due to a failing power steering pump. As the bearings on the impeller go bad it will start to make noise as the pump is turning. If you have a bad power steering pump you usually will also experience leaks from around the pulley, a wobbly pulley, or difficulty turning the steering wheel when you are stopped. If you have multiple of these symptoms together, it is probably time to replace your power steering pump.
Lastly, and most usually, a whining power steering pump is an indication of a low fluid level. Your power steering fluid is probably something you have rarely if ever checked, so it often comes as a surprise if the level is low. Your power steering fluid reservoir is also relatively small so even a slow leak will cause a low fluid level relatively quickly. To confirm this is your problem it is as simple as checking your power steering fluid level. Some power steering reservoirs are clear so you can see through them to check how full they are. You may have to wipe away some dirt and grime to find the "full" line, but it should be easy to check. If you have an opaque power steering fluid reservoir there should be a small dipstick under the cap that will help you measure the fluid level. If it is low, then you have a leak somewhere and topping off the fluid should quite down your power steering pump.
If you discover a power steering leak, rather than simply continuing to add fluid every time it gets low, you should fix the problem permanently so you don't have to continue to check your power steering fluid level. Replacing lines or seals can be a surprisingly difficult task due to the location of your power steering pump and steering gear or rack. The easiest way to seal your leak is to do it from the inside out!

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Power steering whining sqreeching Google Search

It sounds like your car is low on power steering fluid. When the power steering fluid is low, the power steering pump is running dry, which makes a grinding or moaning sound. Check the power steering fluid level and top up if necessary. It should be on the left side of the engine compartment. Your owners manual should have the exact location of the power steering reservoir, and what type of power steering fluid to use.
Good luck
Matt

The noise you are hearing and feeling is very likely due to a low fluid level. I'd suggest you start by filling the power steering reservoir to the correct level with the correct fluid. Cycle the steering from lock to lock a few times to see if the noise gets better or goes away completely. Monitor the fluid level to determine how quickly the fluid leaks out and also to see if you can tell where the leak is coming from.

Be aware though that the longer you drive the car with a low fluid level condition, the more damage you will cause and the more expensive the repair will be.

the rack and pinion unit may have a pinhole leak

it could be low on powersteering fluid, its just vibrating through the colum so you could check that first, or it could be the steering wheel shroud the plastic that covers the colum behind the steering wheel, take it off and see if it still does it,check fluid first though...hope this helps

First you need to verify where the noise is coming from. Squeaking and grinding is bad, like brakes, wheel bearings or ball joints.If you turn ther steering wheel while sitting still, that rules out brakes, or wheel brgs. The leak may be ps fluid, but check the hoses first, thats the most common thing to leak.

The PS system probably has air bubbles in it. The air needs to be bled from the PS hoses and cylinders. You will also find it easier if you turn OFF the A/C when you are parking.
In a safe place (your driveway), Put gear in Park, set parking brake, replenish the power steering reservoir with fluid (not transmission fluid) and start engine. "Work" the steering wheel full counter-clockwise / full clockwise a few times. The "groans" you hear are voids of air travelling / escaping through the system. After it has quieted down, turn off engine, replenish fluid and do once more before test driving. Be sure to replenish fluid before testing / parking.

mine did the same thing. Where the steering column goes through the firewall (floor) there is a rubber seal. That seal has gotten dry. Apply a small amount of lube where the shaft goes through and turn the steering wheel. This helped eliminate my squeal.