Do you hear a loud whine when you turn the steering wheel of your Mercedes-Benz? This may be most noticeable when starting the car or when the engine is cold and is typically caused by low power steering fluid. Not only is this embarrassing; but if the power steering level is low, you should add fluid as soon as possible to avoid causing problems to the power steering pump. This can happen on any Mercedes-Benz model including E, C, S, CL, SLK, ML, SLK and CLK Class.
Watch the video or follow step-by-step directions to learn how to check the power steering level on your Mercedes-Benz or add new fluid.
Required Power Steering Fluid
Before you start
- Park you Mercedes Benz on a level surface.
- Set the emergency brakes.
- Choose the correct power steering fluid for your car.
Steps to check and add power steering fluid
|STEP 1: Start the car and wait until it reaches normal operating temperature. This can take several minutes. Turn the steering wheel from lock to lock a couple of times. Next, open the hood by pulling on the hood release.|
|STEP 2: Locate the power steering reservoir. Clean the reservoir cap with a clean cloth to avoid any debris falling in.|
|STEP 3: Remove the reservoir cap by twisting the cap counterclockwise. If you can’t remove the cap easily, you may find it easier to remove the engine air tube. As you remove the cap be sure to have a rag in hand to wipe off the dipstick. Be careful to not get any contaminants in the reservoir.|
|STEP 5: Reinstall the cap back on the reservoir. Remove the cap again and check the fluid level on the dipstick. If the level is below the MIN mark, add power steering fluid to bring the level up, but be careful to stay under the MAX mark. DO NOT overfill the power steering reservoir beyond the High/Max mark. If you add more fluid you should remove some by using a fluid transfer pump. Once you have the correct level, reinstall the cap and take the car for a spin. Make sure you don’t hear any whining or groaning coming from the power steering. Double check the power steering level, to ensure that the level is correct. |
If your car is at operating temperature, check the fluid level at the upper Max and Min marks on the dipstick, indicated by the 80°C writing. If your engine is cold check the fluid level at the lower marks on the dipstick, Max/Min at the 20°C range.
What kind of power steering fluid to use on Mercedes-Benz?
Always verify with your dealer or look it up on your owners manual the type of power steering fluid that you should use on your car. In most models Mercedes-Benz uses Pentosin CHF 11S fluid. Pentosin power steering fluid is sold at the dealerships but you can buy it for less online.
Check Prices – Find Genuine Mercedes Benz Power Steering Fluid
Symptoms of Power Steering Problems
Power steering pump will typically warn you with an audible noise when it is low on fluid. Here are the top signs of low power steering fluid or power steering pump failure.
Whining or Groaning Noise
Groaning noise are annoying and you can not ignore them easily even if you wanted too. You may initially hear the noise when you turn the steering wheel full clock. As the fluid level gets lower, you will hear the groaning noise almost every time you turn the steering wheel.
Adding power steering fluid to correct the level will typically fix the groaning noise. If it doesn’t the power steering pump may need to be replaced.
If your Make Model is making squeaking noises when you turn on the car, it is a sign that the power steering belt may be old or the power steering pump itself is going bad. Before you replace the pump, change the serpentine / power steering belt. It is cheaper and in most cases it will fix the squeaking noises that you hear in the morning.
Steering wheel is stiff
If the power steering wheel is stiff when you turn it or requires a lot of force to turn, it is a sign that the power steering pump is not producing the required flow to operate the power steering system. Have the car checked. You don’t want to loose power steering when driving. If you do lose the power steering, it will be difficult to turn the steering. You will have a heavy steering.
Applicable Models Applicable Years
|A Class||1997-2004||A160 CDI||A180 CDI||A200 CDI||A170||A200|
|C-Class||W 203||2000-2007||C 320||C 350|
|W 204||2008-2014||C 250||C 300||C 350||C 63 AMG||C 55 AMG|
|E Class||W210||E 430||E 300 E320||E230||E 280||E 320||E550|
|W211||E 200||E 250||E 300||E350||E 500||E63|
|S-CLASS||W 140||1993-1999||500 SEC||600 SEC||S 500||S 600||CL 500|
|W 220||2000-2006||S 350||S 430||S 500||S 600||S 55|
|W 221||2006-2013||S 550||S 600||S 63 AMG|
|CLS-CLASS||W 219||2005-2011||CLS 500||CLS 550||CLS 55 AMG||CLS 63 AMG|
|W 218||2012-Present||CLS 250 CDI||CLS 350 CDI||CLS 300||CLS 350||CLS 550|
|CLK-CLASS||CLK 63 AMG|
|208||1998-2003||CLK 320||CLK 350||CLK 500||CLK 550||CLK 55 AMG|
|CL Class||W 215||2000-2006||CL 500||CL 600||CL 55 AMG||CL 65 AMG|
|W 216||CL 550||CL 600||CL 63 AMG||CL 65 AMG|
|SLK||R 170||1998-2004||SLK 230||SLK 320||SLK 32 AMG|
|R 171||2005-2009||R171||SLK 280||SLK 350||SLK 55 AMG|
|SL||129||1990-2002||300 SL||500 SL||SL 320||SL 500||SL 600|
|R 230||2002-2012||SL350||SL500||SL55 AMG||SL600||SL65 AMG|
|R 231||2013-Present||SL350||SL400||SL550||SL63 AMG||SL65 AMG|
|R-CLASS||V 251||2006-2009||R320 CDI||R 320 BLUETEC||R 350||R 500||R 63 AMG|
|M-CLASS||W163||1998-2005||ML 320||ML 350||ML 430||ML 500||ML 55 AMG|
|W164||2006-2011||ML 320 CDI||ML 320 BLUETEC||ML 350||ML 500||ML 550|
|W166||2012-Present||ML350||ML400||ML550||ML63 AMG||ML250 Diesel|
|G-CLASS||W463||1978-2009||G 290||G 300 D||G 320||G 350||G 500|
Power Steering Fluid FAQ
Should I continue to drive if my power steering fluid is low?
Avoid driving your Mercedes-Benz (C, S, SLK, CLK, M, E-Class) with low power steering fluid. It is better to use a generic Power Steering Fluid, than drive with very little power steering fluid in your power steering pump. You can also perform a power steering flush to replace all of the old fluid from the system.
How often should I replace the power steering fluid on a Mercedes-Benz?
You can always check with the dealer to find out the exact interval to replace the power steering fluid. Our recommendation is to change it every three years or every 75,000 miles.
How much does a power steering fluid change cost on a Mercedes-Benz?
The price to replace the power steering fluid could vary depending on the Mercedes-Benz model and even your location. If you have a repair shop perform the flush expect to pay between $110 and $240 USD.
Why should I change the power steering fluid?
You should consider replacing the power steering fluid because the fluid breaks down and gets contaminated with metal and rubber particles. This can increase the wear rate of the pump and steering components.
Why do I loose power steering fluid?
As the car ages, power steering seals will wear. If you only have to top off the power steering every other year, than you are ok. If you have to add power steering fluid every month then you should have the system checked out and repaired or replaced. Unfortunately, power steering leaks can end up being expensive repairs.