What are the power steering fluids equivalent to the Mercedes Benz power steering fluid?

This article will answer the following questions: what is the Mercedes Benz power steering fluid equivalent? Which power steering fluid is used in the Mercedes Benz? What are the advantages of electric power steering  over hydraulic power steering? How to check the power steering fluid level?

What are the power steering fluids equivalent to the Mercedes Benz power steering fluid?

Mercedes Benz manufactures its genuine power steering fluid but there is much aftermarket equivalent power steering that can be used in the Mercedes Benz cars. Following are some of the aftermarket Mercedes Benz power steering fluids:

Mercedes Benz has always recommended using genuine parts and fluids, power steering systems in the Mercedes Benz cars are complex and operated in a specific pressure range. If the viscosity of the power steering oil is different from the original oil it will damage the power-steering rack or any oil seal on the hydraulic lines.

Mercedes Benz always manufactures all the fluids used in hydraulic systems like power steering, Active body control. Mercedes Benz even makes a proprietary engine and automatic transmission fluid. In this way, the company can be sure that the system will continue to work as designed even after replacing the operating fluids.

Like other German car manufacturers, Mercedes Benz tests and publishes specified oil grades in MB sheet numbers. The MB sheet numbers start from MB230 and go till MB 240, depending on the hydraulic system in the vehicle the correct MB sheet number oil is used.

Which power steering fluid is used in the Mercedes Benz?

The part number of power steering oil used in authorised service centres is A 000 989 88 03. It belongs to the MB sheet number 236.3  and it is manufactured by Mercedes-Benz AG, Stuttgart. 

Mercedes Benz no longer uses the hydraulic power steering system on the latest models in the passenger car segment. Hydraulic racks are replaced by electric power steering. There is an electric motor connected to the power steering rack via a belt. Depending on the speed of the vehicle the motor can support the driver in steering the vehicle.

What are the advantages of electric power steering over hydraulic power steering?

Following are a few advantages of electric power steering vs Hydraulic power steering:

• Less power consumption

The electric motor of the power steering is not working at maximum output all the time. For example, if the vehicle speed is low the motor gives maximum output to the power steering rack and makes the steering vehicle easier to turn. At high speeds, the motor is not working at maximum output and the steering wheel becomes slightly heavier so that the driver can control the vehicle more easily.

The hydraulic power steering also used a pressure regulator solenoid but the pump is driven continuously by the internal combustion engine.

• Fewer components

Hydraulic power steering system needs a hydraulic pump driven from the belt connected to the crankshaft and hydraulic hoses connected to the power steering rack that carries power steering fluid from the rack to the power steering fluid reservoir. The entire hydraulic power steering system is heavy and adds weight to the vehicle.

Electric power steering  is very compact and there are no additional components required. The control unit is integrated into the power steering rack and it is directly connected to the vehicle power supply through a pre fuse box.

The electric power steering is also connected to the vehicle’s onboard communication systems and uses a faster FlexRay communication protocol. Because of fast data transfer speeds, the power steering control unit can make faster changes in the torque output of the electric motor according to different driving conditions. Steering is very responsive compared to hydraulic power steering

• No Power loss from the engine power output

Electric power steering is not driven by the crankshaft, hydraulic power steering has a hydraulic pump driven by the crankshaft, it adds one more  ancillary component connected to the engine and even if the power required for the operation of the power steering pump is not significant it is still a loss as power produced by the engine is used for purposes other than propulsion.

How to check power steering fluid in Mercedes Benz cars?

The power steering fluid required for the hydraulic power steering system is stored in the power steering fluid reservoir.

Depending on the model the power steering reservoir can be located on the hydraulic pump or the left side of the engine compartment. Follow the following steps when checking the power steering oil:

• Locate the power steering fluid reservoir and unscrew the cap only when the engine is turned off.
• Make sure the steering and front wheels are pointed in a straight direction.
• There is a dipstick attached to the bottom side of the cap with two marks corresponding to the operating temperature.
• Dip the dipstick in the power steering reservoir but do not screw it, hold it at a straight level for a few seconds and then take it out.
• Check the level of power steering fluid, it should match the marking on the dipstick according to the current temperature.

Few Mercedes Benz models use hydraulic suspension and there is a hydraulic fluid reservoir near the power steering fluid reservoir. Do not get confused between the two fluids as mixing the two fluids will damage the hydraulic suspension system.

The power steering fluid is yellow and the hydraulic oil used in the Active body control system is blue. 

Other articles about Mercedes Benz you may be interested in

Which is the most reliable model in the Mercedes Benz C Class?

What is the resale value of the 1975 Mercedes Benz SL?

Should you flush the Mercedes Benz radiator?

Conclusion

The power steering fluid sold at the authorised Mercedes Benz dealership by part number A 000 989 88 03 can be expensive compared to a few other alternatives available in the market. The availability is also a factor in the international markets, therefore follow the MB sheet number. As long as the power steering oil is included in the MB sheet number 236.3 it can be considered equivalent to Mercedes Benz power steering fluid