Need to flush Hydraulic Fluid.
 

I have a 500e and i'm replacing the right rear shock so I thought I may as well flush the hydro fluid. Anyone have a walk-thru, what fluid should I buy and from whom. Is there synthetic, I've swithed everything else. Thanks.

There is a bleeder on the height valve in the rear. I think I would put a line on it and open it. Turn the motor on and collect what runs out. Keep adding at the reservoir. Once you have it as clear as you would like, close the bleeder and let it pump up. Shut the motor off and open the bleeder again this will allow most of the fluid to come out of the accumulators.

I wouldn't worry about the fluid in the struts as one would be new. I might do the basic flush before removal so new fluid would go into that strut.

The fluid is a mineral hydraulic oil and is supplied by a number of manufacturers including Pentosin and Febi, aside from MB. The same fluid is used in Jags, BMWs and Audis, although there are at least two different fluids used for BMW and Jag, depending on the system.