Let me "fan" this fire a little bit. Last year the fan clutch on my '91 300SE locked up due to a dry bearing. Once I got the clutch and hub off, it was winter by the way in Georgia, I drove around with only the aux fans. They never kicked on and the temp never climbed much above normal, even in town. I bought an electric fan rated for a V8 engine, did some engineering with a genuine Benz fused relay out of a wrecked car, wired it (soldered) through the A/C circuit at the compressor, now I have the needed cooling when the A/C is on. I can hear the aux's kick on but this is normal in summer when running A/C. I've noticed that I get a little better mileage due to the engine not having to pull the fan. My 2 cents

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1991 300SE (my ride, 279,000 miles, looks almost new
1954 Cadillac (21 yo son's car, he bought when age 15)
1972 SeaBird 19 ft runabout (old but solid, slant six, Volvo sterndrive perfect condition, undergoing complete overhaul and refit)
1998 Toyota Rav4 (my sons daily driver when he is in the Continental US, PROUDLY serving in US Navy)