did it yesterday and I can't believe how much difference its made. The old fluid was black for sure. Not only does the car going up and down much faster than it did before, I swear the ride quality has improved, noticably. Is that even possible? I understand the bias to feel the results of work that we've done, so maybe. Anyway, for a 30 minute job it's no brainer. 1/2" barb and 2' of 1/2" hose. And a bucket.

 

I flushed the ABC like you have 6+ times. It does help but you don’t actually get the fluids behind rear valve block to flush unless you crack a rear bleeder valve. When I replaced the rear Accumulator I found old black fluid.
Doing a flush off the return line to the tank is better than nothing but the rear valve block (and lines behind) need a bleed to dump the old fluid.
Even after pushing 2 L thru the rear system it still was slightly discolored just not black.
You’re fighting the pressurized Accumulator that stores a fair amount of fluid
I got the car with >80k mi on it and maybe if the original owner had done at least one/two full flushes it would’ve helped but my main problem was the front valve block/struts and the entire electrical control system.
Any fluid flushing helps. Keep up the good work

 

Do you drain with with the car running or off?

 

Car has to running and best done by two people; One to turn the car on and off while someone cracks the valve. You have to be careful not to drain the entire system and have the hydraulic pump go dry

 

old ABC fluid carries a lot of metal in it, its acidic, it thickens which causes wear to seals and the pump from trying to push it around, and it heats up faster which is a compounding issue

most ABC issues are preventable in the long run with regular maintenance of the fluid and accumulators. its a special interest area of expertise for me here locally

 

I am preparing to change the rear accumlator and valve block. When should I do the flush before or after I change the accumlator and valve block?

 

are we talking about bleeders on each shock absorber or somewhere else?
If the shocks is lt like bleeding brakes? Furthest from pump first??
And can you just bleed the shocks (or wherever) and just replace that amount of fluid? (not total replacement of system fluid)