Power Steering: Types, History, and Essential Care

Power steering, initially used to facilitate the handling of trucks and buses, has become an indispensable element in modern automotive mechanics. It significantly improves both the driving experience and safety. This leads us to the question...

What is Power Steering?

Essentially, it is a mechanism that amplifies the force applied to the steering wheel by the driver, reducing the physical effort required to turn. In other words, it is the system responsible for helping the driver steer the vehicle smoothly and effortlessly.

A Bit of History...

In 1926, Francis W. Davis patented the first hydraulic power steering system. However, manufacturers did not implement this technology until 1951, when Chrysler introduced a hydraulic system called Hydraguide in its Chrysler Imperial model.

Types of Power Steering

Currently, there are three main types of power steering systems:

• Hydraulic Power Steering: One of the first to exist and now one of the least common in new cars. This system uses a hydraulic pump to maximize the driver's effort. Since the pump is driven by the engine's power, the system only works when the engine is running.

• Electro-Hydraulic Power Steering: The logical evolution of the hydraulic system. It also uses a pump to move the steering mechanism, but instead of being powered by the main engine, it is driven by an independent electric motor. Like the standard hydraulic version, it relies on fluid passing through a piston to balance pressure as the driver turns the wheel.

• Electric Power Steering (EPS): Currently the most widely used system. Instead of a hydraulic pump, it uses an electric motor installed directly on the steering column. Based on signals received from the ECU, the motor assists the driver in turning the wheel. Its main disadvantage is a relative lack of power, which is why it is rarely used in heavy-duty vehicles.

Because EPS is a fully electronic system with its own control unit, it cannot be repaired without specialized diagnostic equipment, which can make repairs more complex.

Care and Maintenance

It is important to clarify that only hydraulic and electro-hydraulic systems require regular fluid maintenance. The recommended care includes:

• Check Oil Levels and Purity: These systems function using a specific power steering fluid. It must be topped up and replaced periodically according to the manufacturer's specifications.

• Inspect the Drive Belt: If you hear squealing or feel vibrations during quick turns, the belt may be loose or contaminated with oil.

• Avoid Forcing the Steering: Do not hold the steering wheel at full lock (turned all the way to one side) unnecessarily, as this puts extreme pressure on the pump.

Although Electric Power Steering (EPS) does not require fluid maintenance, it still benefits from these general recommendations:

• Regularly check tire pressure.

• Avoid maneuvering the wheel while the brake pedal is fully depressed.

• Avoid sudden, violent jerks of the steering wheel.

At Ecumotorstock, we specialize in the professional repair of Electric Power Steering systems.