I would recommend checking the sending unit for the temprature gauge. If you have replaced all these items the only other problem could be a blockage somewhere, but I would check the gauge. I have noticed my SL320 running hotter lately, but it is still within the operating range. I have replaced my water pump, thermo, and radiator. I was thinking about the fan clutch, but I am going to check the gauge first. I will let you know what I find.
Brian

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Brian W. Heitman

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