Signs You May be Low on Power Steering Fluid

Steering wheel
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Your can exhibit a number of symptoms when the level of power steering fluid is low in the reservoir. If you are experiencing any of the following problems with your car's power steering, you should check your power steering fluid, it may simply be low! It's easy to add power steering fluid, too.

Symptoms of Low Power Steering Fluid:

  • Noisy steering. If your power steering is making all kinds of noise, especially when you are moving slowly, like in a parking lot, check the fluid level in the power steering reservoir. 
  • Jerky or jumpy power steering. Sometimes your steering wheel will feel jerky as you try to turn it smoothly from one direction to the other. This will be most noticeable in a parking lot moving slowly or not at all. 
  • Hard to turn the steering wheel. As power steering systems lose fluid, they work less efficiently. Eventually, you'll start to feel the difference on the steering wheel end, making it much harder to turn the wheel than it normally is.
  • Screeching steering. If it sounds like cat fighting (or cats mating) under your hood when you turn the steering wheel, you may need to check your power steering fluid. 
  • Puddle or stains under the vehicle. If you notice a puddle under the vehicle in your usual parking spot, it could be power steering fluid. Although any number of liquids might be the culprit, power steering fluid is a prime candidate. 

How Power Steering Works

Your power steering system relies on principles of hydraulics to do its work.

The principles are similar to the way your car's brake system works. Most power steering system are better described as power-assisted steering, since a direct mechanical linkage between the steering wheel and the road wheels is still present. In the power-assisted steering system, the car's engine power pumps a type of hydraulic oil—power steering fluid— from a reservoir to the steering box via a belt and pulley.

As you turn the steering wheel, this pressurized fluid is allowed to flow into a piston that gives additional push to move the steering in the desired direction. When you stop turning the wheel, the valve shuts off, the oil no longer flows, and the pushing assist of the piston stops. If the power to the system fails, the steering wheel can still turn the car's wheels, thanks to the fact that direct mechanical linkage still exists, but the feel of steering will be much heavier. 

Monitoring Power Steering Fluid

Power steering fluid is a hydraulic fluid. Most types are based on mineral oil, although some are water-based. The power steering fluid levels should be checked at every oil change, and most experts recommend that the fluid be drained and replaced about every 60,000 miles. In normal use, fluid levels should really not go down, so if you begin to notice that additional fluid is needed regularly, keep a close eye on the levels, as a serious leak may be the cause of the problem.