MERCEDES-BENZ ML Hydraulic power steering pump

What is a power steering pump?

One of the central components of the steering system is the hydraulic power steering pump, which makes the steering system more comfortable and soft. This mechanism ensures movement along the selected trajectory and creates the necessary "feedback" between the steering wheel and the wheels during driving. If the power steering pump was installed only on the most expensive cars in the last century, now it has become the standard for vehicles. 

What does the power steering pump consist of and how does it work?

There are three types of steering systems: 

• hydraulic-start simultaneously with the engine and use a special liquid in operation;
• electric-work thanks to the energy of the generator and does not require the use of fluids, like hydraulic ones;
• pneumatic-work based on a compressor, installed only in trucks and buses.

The design of the power steering system includes a mechanism that interacts directly with the steering mechanism, a working fluid tank, and a control system. Inside, a rotor is installed that constantly rotates and creates pressure so that liquid gets into the steering mechanism and makes its turns smoother. 

The power steering pump operates continuously, even when the vehicle is moving in a straight path and the driver does not turn the steering wheel. Its spontaneous rotation is prevented by the liquid contained inside the system and evenly distributed between the two chambers. 

When do I need to change the power steering pump?

Only an experienced mechanic can confirm the malfunction of this mechanism, but any driver can pay attention to the following symptoms that indicate problems in the operation of the power steering pump:

• To rotate the steering wheel, you need to make more effort than before. 
• During control, you can hear the characteristic "howl" of the system, which runs out of liquid. 
• There is a backlash on the steering rod, which is especially felt during turns.
• The steering wheel vibrates almost constantly when moving in a straight path and when cornering

How do I restore the power steering pump to Operation?

You can repair the mechanism or completely replace it. Experts advise giving preference to the second option — replacing the pump is most appropriate and correct in all cases, except when the problem is eliminated by refilling the hydraulic fluid. 

STS specialists.Parts will help you choose the best power steering pump for your vehicle in terms of properties and cost, perform all the necessary work, and provide recommendations for further operation of the mechanism. We also have relevant experience and our online store with a large warehouse of products, particularly everything you need to repair steering, air conditioning, turbochargers, and fuel systems. We provide a guarantee for all types of work! 

Contact us in Warsaw (Poland) at the address: Plochochinska STR., 91, 03-044. call +48 22 481-58-28 to get professional advice and book a visit time.