I've seen at least 2 or 3 complaints from people that had to get theirs replaced multiple times to address it, some as many as 3 times. Certainly look around elsewhere, but it's not impossible that it could still be the culprit.

--Matt

I'm surprised nobody has mentioned your water pump going bad yet. :D

Yes, it is the water pump going out on you. my '10 MCS with 28000 did that when it was replaced.

I changed the pump and the sound is still there

Did you ever figure out what was causing the squeal/whistle ?

Cheers

I have the same problem, replaced serpentine belt, friction wheel and water pump. Seemed better for a while but then came back. Have decided that it's coming from the engine cover/PCV. Stops when opening the oil filler cap or loosening the dipstick. Maybe this information can help someone else 🤔

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