For high profile fans, you can use heavy duty relay kit P/N 30247. If you got a thermostat above 160 degrees (say 180 thermostat), your engine will not get cool enough for the fans to shut off. Dual Electric Fan Relay Kit Radiator Electric Cooling Fan Thermostat Kit Temperature Sensor Switch 185 On 175 Off, 40 AMP Waterproof Relay Kit.
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