Attn all 163 ML owners - This is a need to know

[MLSL]

We have a 2000 ml 320 and the other day it developed a serious whine in the power steering system. I have read numerous posts on this and there were stories of pump replacements, rack replacements, lubrizol etc etc. Many had dealers replace all of the components and still had the whine.

I told my MB Tech friend of the symptom and he asked me if while the engine was running did I see fluid swirling in the fluid tank, I cant spell reservoir. Fluid was swirling rapidly when I looked in it so he advised me to replace the reservoir. I did and the whine was gone totally. Cost was about $45.00. I am sure if I took this in it would have cost a fortune. Use a kitchen baster to remove most of the fluid from the tank before removing it. Also put some rags around the pump to catch the rest of the fluid. Buy your own new baster, $2.00, so your wife doesn't kill you. To get extra reach into the tank, I slipped a 3"piece of rubber fuel line onto the baster which helped me get mst of the oil out.

To get tank off 1. Remove front torx bolt 2. remove rubber hose on corner of tank and elevate it to keep fluid from spilling 3. remove big circlip on back of tank 4. Slide tank forward to remove.

Note: Use new MB o-ring where circlip goes buy it when you buy the tank.

Reverse the above to install then fill to proper line with new fluid. Good luck

Sorry to Sosh - some of us really like fixing things without being taken.

[fabbrisd1]

The reservoir replacement has worked well witrh me with (3) MB's I owned made between 200-2003...

My indie has said no one would believe the fix, some people term the whine a result of "cavitation" like a boat propellor.... but worked for me.

[Darkmann]

Great tip!!!!! I wish I knew this b4 my last of 4 rack replacements. Now if the problem reoccurs, I know what to do. BTW, I think MB believes it's cavitation also, just that their solution is very expensive and often does not resolve the issue.

[mercutio80]

This may be a dumb question, but is there any difference between the old reservoir and the new one? Is it the exact same part or is there a modification that is fixing the whining problem? If it is an MB part...do you have the part number? Thanks

[hockeyelmo]

This may work temporarily as it did with my truck; I took it into the dealership and they replaced the reservoir and hose- and it was problem free for a week, but soon enough you'll find that most steering "whine" issues have to do with more serious leaks - from the rack's o-rings or a bad hose connection.. the whine is just a symptom of low fluid in the reservoir which in most cases entails a more serious problem..

I'm not a technician or anything but I'm lead to believe that there is an inherent flaw with the ML 163's power steering- there's too much pressure in the system which leads to leaks in key parts of the pump or rack.