Motor vehicles originally relied on the driver's strength to turn the wheels around corners. Before power steering systems were put in use, vehicles relied on geared steering systems that required many turns to adjust their driving direction, and driving was more difficult and far more work than it is today, thanks to power steering systems. Today, two different power steering technologies are in use, and it's interesting to explore hydraulic vs. electric power steering, how the systems are different, and which is superior.
What is Hydraulic Power Steering
Hydraulic power steering has been a patented concept since 1876, but it wasn't put into use on commercial vehicles until 1951. Still, we've had hydraulic steering systems for more than 70 years now, and they're still being used today. Hydraulic steering is a special system designed to make turning the wheels of your vehicle far easier. Through the use of a hydraulic system, it's much easier to turn than it otherwise would be.
How Hydraulic-Powered Steering Works
Hydraulic power steering relies on principles of fluid dynamics to make turning your steering wheel easier. We won't go into all the science behind the system, but essentially, you have a piston that's built into your vehicle's steering rack. Fluid pressure levels are adjusted at one side of the piston or another. As the pressure levels on either side of the piston move, a huge amount of force is developed, either left or right.
By coordinating the operation of a hydraulic fluid pump with your steering direction, automakers created a system that generates hydraulic pressure to assist in turning a vehicle almost immediately after you begin turning your steering wheel. All sorts of extra refinements have been made to this power steering system over the decades, but the idea largely remains the same, and it works well. Hydraulic systems have been getting replaced by electric power steering systems lately, though, because they help improve fuel economy values.
What is Electric Power Steering?
Electric steering is a type of steering assistance that makes turning left or right far easier than it would be if you manually turned your vehicle's wheels yourself. Electric power steering systems were first added to vehicles in 1989 and can be found on Pontiac Fiero models. However, this steering system remained uncommon until recently as automakers try to make their vehicles more economical. The specialized system automatically engages a powerful motor to aid in adjusting your vehicle's wheel direction whenever you turn your vehicle's steering wheel. The system is more advanced than that simple explanation, but if you understand that, you have a basic idea of what's happening when you turn in a vehicle equipped with an electric steering system.
How Does Electric-Assisted Steering Work?
While a hydraulic system takes rotational power from the engine to power a hydraulic pump to move hydraulic fluid around, an electric steering setup relies on battery power to turn a servo motor to move the car's steering rack left or right. As you turn your vehicle's steering wheel, a motor is engaged to smoothly apply power to your car's steering system in the direction you intend to turn. The steering system can function smoothly thanks to help from a computer system and a torque sensor that can detect how much force and in which direction the steering wheel is turned. All the inputs going to the intelligent steering computer determine how much force is applied by the motor that powers the electric steering system to give you reliable steering action as you turn. The system delivers smooth steering results, but some people believe the steering feel delivered by these systems isn't as good as what hydraulic steering can offer.
Steering Feel Versus Fuel Economy: Hydraulic vs. Electric Power Steering
Most automakers are aggressively pushing for electric power steering because using such a system allows improvements in good gas mileage. A hydraulic steering system relies on the engine's rotational power for operation. Taking even just a bit of power from the engine reduces fuel economy values by around 1 MPG (mile per gallon). That's a significant decrease in fuel economy and something automakers aren't willing to sacrifice when they're fighting to make vehicles as fuel-efficient as possible.
Even though electric steering setups are better for fuel economy values, many drivers prefer the more natural feel of hydraulic steering systems. According to automotive enthusiasts and experts alike, hydraulic steering systems are more refined and deliver superior feedback and road feel to drivers. The steering system is one of the main ways drivers can feel what's happening with a vehicle. This makes superior steering feel a significant factor that should not be overlooked.
While it's unlikely that hydraulic steering systems will continue to see use in the coming decades, it's vital that electric steering setups are improved to make them feel better. Automakers must continue to refine the designs of electric steering setups to enhance road feel and to help them rival hydraulic systems in terms of feel. Since electric power steering systems are relatively new, it's likely they will continue to improve, and we suspect they will eventually feel as good as their hydraulic counterparts. Until then, some drivers will try to get vehicles with hydraulic steering, and a few automakers will likely continue to supply them until they can't afford the fuel economy losses any longer or the demand dies down.
There is No Clear Winner
It's impossible to choose a clear winner for the battle of hydraulic vs electric power steering because both systems are functional and both are used on modern vehicles with good results. What you pick ultimately depends on you.
If you care about fuel economy above all else, you'll prefer electric steering systems. If you want the best possible steering feel as you drive, a hydraulic system might be the option that you go for. To find out which version a vehicle has, a vehicle history report makes seeing the original specs easy.
Either way, both options currently exist, and you can technically get either system you prefer on your vehicle. Electric-assisted steering is far more common today, though, and it's only going to become more common as automakers continue to push for better fuel economy values over time.