RC:

Mine in the E63S always stays like yours around the middle (90°C), so it should be OK.

Why would you think 90°C is too low? 

That's oil you're talking about, he's talking about water (53°), which indeed seems low to me?


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1969 Mercedes-Benz 300SEL 6.3  / 2008 Porsche 911 GT3 RS (sold) / 2011 Mercedes-Benz C63 AMG Performance / 2014 BMW-Alpina D3 biturbo Touring / 2018 Porsche 911 GT3 Clubsport