I'd suggest runing a search, there's very long threads about this topic.

On my car I just ran PS fluid through the system and keept flushing it until it stayed clear (the PS fluid I chose was clear). The PS fluid is so cheap this wasn't a problem.

-Jason

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.