My '94 E320 wagon started to overheat. I read all the threads on the subject and it seemed to be caused by the fan clutch, but just to be sure, I cranked the drive belt a bit tighter and it cured the problem instantly.
The belt is not the easiest thing to evaluate without the proper lighting condition and it may seem tight. Mine was well worn on the interior side and it felt tight, but it surely was slipping.

I'd advise all with an overheating problem to first consider tightening the belt. It's the cheapest fix.

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'76 240D-Sold
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'64 Porsche 356C Cabriolet- under restoration
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'06 E350 Wagon, 84K Miles
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