That's bad. Did you check the oil level? You most likely ran it low on oil. How long since you last changed or checked it?

The engine is probably toast.

"Supremely reliable" yes, but only if it is maintained Its not a magic car that will just run forever with 0 care or maintenance.

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-diesel is not just a fuel, its a way of life-
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'13 ML350 Bluetec - 95k - dad's (OC-98k)
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