Could it be related to the extra back pressure the pump is required to deal with? I have the series 1 - 72 row which supposedly has less back pressure due to having a lot more rows that are short (mounted sideways, oil flows top to bottom) with a non-thermostatic plate and I don't hear any noise ever. But then with all the other noises the car makes such as ECU wine, fuel pump wine, transmission input shaft rattle, I could just be missing it.
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