I wouldn’t worry about the plastic. Today’s plastics are very heat resistant. My 2017 VW Alltrack has plastic all over its engine. Very common…

Search here to see if you can find the part. You probably will. If not call FCP Euro and ask about it. They are usually very helpful. If you own a Volvo you really need to be willing to dive and do some internet searching sometimes.

https://www.fcpeuro.com/Volvo-parts/S40/Oil-Filters-and-Lubrication/?year=2003&m=20&e=2007&t=5&b=5&d=57,794&v=

Per Bill’s question: So you never found the source of your PS leak? Updating people who are willing to spend time helping you is a common courtesy. As I said earlier, one step is to flush the system and replace the PS fluid with the correct synthetic fluid for your PS system. That might stop the leak and is good maintenance practice anyway. If your fluid hasn’t ever been replaced it is 21 years old and long overdue.

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Will I buy another Volvo??? We'll see....