ML63 power steering pump?

[zenman63]

Just picked up my 2009 ML63 and it has a pump that needs attention.
Anyone done this, and where is it?

 

[zenman63]

I fitted a new pump around a month ago and not a bad job to do, MB parts found to be the cheapest and very common part.
The noise was reduced but not silent as you would expect, changed the fluid a couple of times to get it green as it should be but 1000 miles later it was back with a wine.
I had read on the forums that the W156 engine also in the C63 etc had a screen inside the reservoir so I ordered one at MB for £37 it was worth a try and sure enough it worked.
New Reservoir fitted and 100% fixed it, its now silent .

I cut the old one up to see the screen and sure enough it was thick in black paste so causing restriction in flow and then cavitation.

 

[Bobby Dazzler]

Thank you zenman63

Recently an occasional murmur which had been there for a while, started to get worse and more consistent. A new pump improved things, but it still wasn't right. Reservoir now replaced (thanks to your post) and the steering is now smooth and quiet.