If you were to jump behind the wheel of a car built in the 1950s or before, you’d notice a lot of changes from our modern technology. While you could quickly adjust to seat comfort, noise levels, or even the lack of accessories, the one thing you might have problems with is the way the car drives.
Power steering may just be one of the single most effective systems adding into the modern day driving experience.
Without power steering, steering wheels were much larger in size. That was to give the driver leverage when trying to turn the wheels. As power steering was added, it became easier than ever to control the wheels with just slight variations of the steering wheel. It shrunk in size to add more comfort to the passenger cabin.
The power steering wheel
The original power steering wheel was added to enhance the feel for the driver. When you have more control, it reduces risk.
To create movement in the steering system, it’s achieved with a gear system. If you’ve ever heard the term “rack and pinion”, it’s referring to the steering system.
The rack is linear rather than round. It’s long and flat with prongs on one side. The rack is attached to the steering column by a series of tie rods.
The pinion is a circular gear that connects the steering shaft to the steering wheel. As you turn the steering wheel, the pinion rotates, moving the rack back and forth to control the vehicle to turn left or right.
The difference between hydraulic and electric power steering
While power steering changed everything, since it was first introduced in the 1950s, it has seen its share of changes.
The rack and pinion gear is also referred to as hydraulic, or HPS (high pressure steering.) These are considered steering assistance programs. If something happens to the engine, these steering assistance systems will give the driver control to steer even if fluid isn’t being supplied to the steering gear. Hydraulic steering uses the power supplied from the engine uses a belt attached to a pump, which continues to circulate fluid throughout the system.
Power flows because of the fluid. The power steering pump circulates this fluid under intense pressure, moving the pistons that control gear shifting, requiring less effort from the movement of the steering wheel. Pressure builds, the piston moves, and you have the ability to shift the car left or right with gentle motions. With technology, this process has sensors which can also take into consideration the vehicle’s speed, which ensures all movement is appropriate for the rate at which you are traveling.
Electric power steering, or EPS, is a bit simpler thanks to technology. It’s the vehicle’s computer system that is in charge of the steering process. The vehicle is equipped with a small electric motor either on the steering column or on the steering rack. Because the EPS doesn’t rely on power from the engine, it can increase fuel efficiency as well.
As a driver turns the steering wheel, the computer translates the movement and sends the request to the electric motor. This moves the rack and pinion back and forth. It’s built similarly to the hydraulic system in that it increases sensitivity at higher speeds. Because the only fluid in the system is to move the rack and pinion, it does not require fluid flushes as the hydraulic system does.
Common power steering problems
Like every part of your vehicle, the car is designed to give small warning signs as to when your power steering is failing. Watch for:
Power steering fluid leaks – power steering fluid is used to transfer pressure within the system, and change the direction of your wheels. If this fluid system has been compromised and is leaking fluid, the ability to build up enough pressure to move the wheels will be harder to do. You’ll notice it in the turning radius of your steering wheel – what used to be simpler grows harder to process. You can easily spot a leak because you’ll notice fluid dripping from the vehicle. There is often a grinding noise that is heard as you attempt to turn. If you ignore the problem to the point the system runs out of fuel, it can burn out the power steering pump.
Worn out hose – all parts are submitted to extreme conditions as you drive throughout the year. Often, one of the first to go are hoses as they crack, peel, or break. If the rubber hardens, it suffers more under intense conditions. This can be one of the first sources of a power steering fluid leak.
Slipped belt – occasionally, the drive belt will slip off the power steering pump. You’ll notice this by a squealing sound as you move your wheel to the left. This will prevent your car from changing direction as the pump won’t be able to do its job because of a total loss of fluid pressure.
Worn out pump – as a car ages, it causes the power steering pump to wear down. The seals can fail, the pump can break down, all leading to a loss of fluid pressure. The squealing noise will increase as you use it, and you’ll eventually lose the ability to steer at all.
How do you prevent problems with your power steering?
Preventative maintenance is your best course of action. Through a routine inspection, one of our mechanics can test each system and determine where weaknesses lie. You’ll learn which parts should be replaced, what signs to watch for, and be able to make decisions about the risk levels of your auto.
Want to keep your family safe every time you get in behind the wheel?
Schedule a maintenance inspection today.