1992 K1500, my power steering is extremely stiff. there is no grinding or whining noise coming from the pump as I would normally expect to hear from a bad pump. Thought I would check here before I spent the money replacing the pump. Any ideas of anything else that could cause this problem?

Whinning Causes
The whining noise you hear coming from the power steering pump is one of three things. The first is more of a loud "hush" than a whine; this is the sound of fluid rushing through the bypass valve when you turn the wheel all the way to one side or the other. Sometimes the bypass valve malfunctions or doesn't open all the way, causing pressure to back up in the pump and cause your engine rpm to drop. The second and third causes result from cavitation -- vacuum pockets created behind the rotor's vane blades as a result of extremely high pump action -- or air in the lines.

Sounds like the power steering pump has failed.
You could take the serpentine belt off and check the pump pulley.

The power steering pump is bad! God-Bless! or the rack and pinion leaks, check the pump first. the pump whines if low on fluid or bad.

sounds like power steering pump is shot.If it ran out of fluid and there is a leak somewhere else,it will burn the pump up.

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

When you hit your brakes does your steering wheel shimmy a little bit? If not it is most likely your bearings in your wheel have gone bad. If it shimmy's it also could be your ball joints.

replace the power steering pump and check for any other power steering leaks (bad pump , low steering fluid )

Do you hear noises while turning the wheel at low speeds or stationary? If you hear a whining noise check the power steering fluid level. A low fluid level would make a whining noise as well as cause stiff steering. If you hear a squealing noise check the power steering belt tension. A slipping belt would cause stiff steering also. If you hear no abnormal noises check to make sure the power steering belt is there. If all of the above check out ok you may have a bad power steering pump, steering gear or a blockage in a pressure line.

normally, the only part of your automatic transmission that will make a whining noise is the pump. it usually whines when iether the fluid is low or more commonly when the transmission oil filter is getting plugged up.

the power steering pump will also make a whining noise too.

turn the wheel all the way to the right and hold steady pressure against the stop. this puts maximum force on the power steering pump and, if the power steering pump is the one making the whine, it will change the sound of it. (usually louder).

if the trans pump is making the whine noise, it should sound different in neutral compared to drive. this test will really only work if it make the noise without the vehicle moving. if it wont do it at idle hold the rpms at 2000 or so.

if you decide the noise is coming from the transmission, and the transmission filter has not been replaced (assuming you installed a used transmission), replace the filter by removing the oil pan.



oh and also, if it is the power steering pump you should be able to make it make the whining noise while the vehicle is stationary. if it wont make noise unless its moving its not the power steering pump.

Checking the level of the power steering is a good start. The pump is mechanical, driven by the serpentine belt, and cannot be turned off. Your steering may seem normal but if you let it go, low fluid can destroy the pump.