If you can see or feel coolant boiling in the tank - your radiator cap is either a wrong type or bad.

If you are sure its good - and you see that your engine fan is not roaring when the engine accelerates at such hot engine temperature - your cooling fan clutch is shot.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)