When I did this job on my 420sel, the old fluid was dark and brownish in color looking like original fluid. So I bought some bottles of PSF from pep boys. The fluid I bought was clear and looked like laundry soap. Well anyways, after flushing and flushing, I got tired of repeating the method and stopped. I topeed off and made sure system was full. So at that point, my fluid is still dark but light enough to see the filter. I am guessing that I didnt get %100 fluid out but I know I got most of it out. I think in order to get a complete %100 flush, you have to repeat the flushing steps A LOT of times!

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2001 E55

2001 E320 Sedan

2001 Subaru Legacy

2006 SLK280

2016 Subaru Outback 3.6