on my 606 engine, it will shoot for the 100C mark without a problem even in the winter of Houston, which is the summer for you in UK.

mine is the NA engine - so it has an 85 degree thermostat in it, it maintains a 90C temperature at all times.

The fan clutch kicks in at quite high temperature, usually near 100C sitting idle, the clutch soaking up the heat. It gives a loud audible roar to let you know its working.

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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)